End face polishing device for optical fiber ferrule

ABSTRACT

The present invention provides an end face polishing device capable of improving a polishing accuracy by polishing an end face of an optical fiber ferrule with adjusted polishing pressure. An end face polishing device  1  for optical fiber ferrule for polishing an end face of an optical fiber ferrule by applying a polishing pressure between a polishing plate  5  driven by a polishing drive shaft and an optical fiber ferrule held by a holding portion  9 . The end face polishing device for optical fiber ferrule has: a bearing portion for allowing the polishing plate  5  to rotate relatively around the polishing drive shaft and to move relatively to the polishing drive shaft in an axial direction; a polishing plate guide supporting portion  31  for movably supporting the polishing plate  5  on a base portion  3  to apply the polishing pressure to the holding portion  9  by allowing the polishing plate  5  to move in the axial direction; a pressing drive source  15  for adjustably outputting a driving force to apply the polishing pressure; and a pressing force transmission mechanism  21  for transmitting the driving force output from the pressing drive source  15  as a pressing force in the axial movement direction of the polishing plate  5.

TECHNICAL FIELD

The present invention relates to an end face polishing device for anoptical fiber ferrule used for polishing an end face of the opticalfiber ferrule.

BACKGROUND ART

An end face polishing device for an optical fiber ferrule described inPatent Document 1 has been conventionally presented.

The end face polishing device described in Patent Document 1 has aholding portion arranged to face an upper part of a polishing plate. Theholding portion has a disk-shape base for holding a ferrule, and thebase is movably supported. Since the base is movably supported, the baseis pressed and moved downward. The base is pressed and moved by a coilspring installed in a center portion of the base side. The coil springhas a configuration to energize the base downward.

Therefore, the end face of the optical fiber ferrule supported by thebase contacts a polishing material such as a polishing film on thepolishing plate with the pressing force while receiving the compressiverepulsive force generated by the coil spring. Since the end face of theoptical fiber ferrule contacts the polishing material with the pressingforce, it is possible to apply the polishing pressure to the end face ofthe optical fiber ferrule with respect to the polishing material. Thepolishing pressure applied to the polishing material contributes toobtain the optical fiber ferrule excellent in polishing accuracy.

However, in the above-described structure, since the pressing force isapplied by merely the coil spring, the base may move by a polishingreaction force and the polishing pressure may be unstable, which mayprevent the improvement in the polishing accuracy.

On the other hand, Patent Document 2 discloses a device for grinding andpolishing workpieces by setting the processing pressure using an aircylinder.

The polishing device described in Patent Document 2 has a lower platenthat is rotatable and an upper platen that is rotatable in the clockwiseor counterclockwise directions at variable speeds. The upper platen isrotatable in the clockwise or counterclockwise directions at variablespeeds by use of a rotational shaft that is connected to the upperplaten and penetrates the shaft center portion of the lower platen. Theupper platen is moved upward and downward with respect to the lowerplaten by the action of air cylinders that are connected to the rotationshaft system.

Accordingly, the upper platen is moved downward via the rotation shaftby the air pressure and applies the predetermined processing pressure tothe workpiece between the upper platen and the lower platen.

However, the above-described configuration cannot have been simply beapplied to a polishing of optical fiber ferrules since the upper platenrotates.

PRIOR ART DOCUMENTS Patent Documents

Patent Document 1: Japanese Patent No. 2787293

Patent Document 2: U.S. Pat. No. 5,697,832

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

In the case where the polishing pressure is applied by use of merely thecoil spring, the polishing pressure varies, which causes a problem toprevent the improvement in polishing accuracy. In the case of thepolishing device capable of applying the predetermined processingpressure, the problem is that the device cannot be simply used forpolishing optical fiber ferrules.

Means for Solving the Problem

The present invention relates to an end face polishing device foroptical fiber ferrule capable of polishing an end face of an opticalfiber ferrule with an adjusted polishing pressure to improve a polishingaccuracy. The end face polishing device for optical fiber ferruleapplies a polishing pressure between a polishing plate driven by apolishing drive shaft and an optical fiber ferrule held by a holdingportion. The end face polishing device for optical fiber ferrule has: abearing portion for allowing the polishing plate to rotate relativelyaround the polishing drive shaft and to move relatively to the polishingdrive shaft in an axial direction; a polishing plate guide supportingportion movable only in an axial movement direction of the polishingplate for movably supporting the polishing plate on a base portion toapply the polishing pressure to the holding portion by allowing thepolishing plate to move in the axial direction; a pressing drive sourcefor adjustably outputting a driving force to apply the polishingpressure; and a pressing force transmission mechanism for transmittingthe driving force output from the pressing drive source as a pressingforce in the axial movement direction of the polishing plate via thepolishing plate guide supporting portion.

The present invention also relates to an end face polishing device foroptical fiber ferrule for polishing an end face of an optical fiberferrule by applying a polishing pressure between a polishing platedriven by a polishing drive shaft and an optical fiber ferrule held by aholding portion, the end face polishing device for optical fiber ferrulehas: a holding portion guiding support part for movably supporting theholding portion on a base portion to apply the polishing pressure to thepolishing plate by allowing the holding portion to move in an axialdirection; a pressing drive source for adjustably outputting a drivingforce to apply the polishing pressure; a pressing force transmissionmechanism for transmitting the driving force output from the pressingdrive source as a pressing force in an axial movement direction of theholding portion, wherein the holding portion guiding support part hasaxial movement guides, one end side of each of the axial movement guidesis joined to a post for attaching a polishing jig used for fixing theoptical fiber ferrule, and each of the axial movement guides is movablysupported by the base portion to serve as a part of the pressing forcetransmission mechanism for transmitting the pressing force from theother end.

Effects of the Invention

The end face polishing device for optical fiber ferrule according to thepresent invention has the above-described configuration. Therefore, itis possible to adjust the polishing pressure while the optical fiberferrule is held by the holding portion. This can be achieved in such away that a pressing drive force input from the pressing drive source istransmitted to the polishing plate, and the polishing plate is moved inthe axial direction with respect to the holding portion. Since thepressing force is adjusted, it is possible to apply the polishingpressure between the polishing plate and the end face of the opticalfiber ferrule to polish the end face of the optical fiber ferrule.

Therefore, it is possible to accurately polish the end face of theoptical fiber ferrule by use of the adjusted pressing force applied fromthe polishing plate. This contributes to the improvement of thepolishing accuracy.

It is also possible to adjust the polishing pressure while the opticalfiber ferrule is held by the holding portion. This can be achieved insuch a way that the pressing drive force input from the pressing drivesource is transmitted to the holding portion, and the holding portion ismoved in the axial direction with respect to the polishing plate. Sincethe pressing force is adjusted, it is possible to apply the polishingpressure between the polishing plate and the end face of the opticalfiber ferrule to polish the end face of the optical fiber ferrule.

Therefore, it is possible to accurately polish the end face of theoptical fiber ferrule by use of the adjusted pressing force applied fromthe polishing plate. This contributes to the improvement of thepolishing accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view partly showing an end face polishing devicefor optical fiber ferrule (Embodiment 1).

FIG. 2 is a side view partly showing the end face polishing device foroptical fiber ferrule (Embodiment 1).

FIG. 3 is a perspective view partly showing a bottom surface of the endface polishing device for optical fiber ferrule seen from one side(Embodiment 1).

FIG. 4 is a perspective view partly showing the bottom surface of theend face polishing device for optical fiber ferrule seen from the otherside (Embodiment 1).

FIG. 5 is a cross-sectional view schematically and partly showing theend face polishing device for optical fiber ferrule seen from a frontside (Embodiment 1).

FIG. 6 is an enlarged cross-sectional view partly showing a bearingportion between a revolution drive shaft and a polishing plate(Embodiment 1).

FIG. 7 is a plan view showing a relationship between the revolutiondrive shaft and a self-rotation drive shaft (Embodiment 1).

FIG. 8 is a cross-sectional view schematically showing a variation ofthe bearing portion between the revolution drive shaft and the polishingplate (Embodiment 1).

FIG. 9 is a side view schematically showing a part (polishing plateguide supporting portion and pressing force transmission mechanism) ofthe end face polishing device for optical fiber ferrule, shown partiallyin cross-section (Embodiment 1).

FIG. 10 is a bottom view schematically showing a part (pressing forcetransmission mechanism) of the end face polishing device for opticalfiber ferrule, shown partially in cross-section (Embodiment 1).

FIG. 11 is an explanatory view showing a layout of the pressing forcetransmission mechanism (Embodiment 1).

FIG. 12 is a conceptual diagram showing a locked linkage of a camstructure, axial movement guide, and a thrust ring (Embodiment 1).

FIG. 13 is an explanatory view showing a lifted state and a layout ofthe pressing force transmission mechanism (Embodiment 1).

FIG. 14 is a front view of a polishing jig used in the end facepolishing device for optical fiber ferrule (Embodiment 1).

FIG. 15A is an enlarged top view showing a state in which a pressingmember of the polishing jig is in a locked position (Embodiment 1).

FIG. 15B is a cross-sectional view showing a state in which the pressingmember of the polishing jig is in the locked position (Embodiment 1).

FIG. 16 is a plan view of the polishing jig (Embodiment 1).

FIG. 17 is a bottom view of the polishing jig (Embodiment 1).

FIG. 18 is a plan view showing a state in which the polishing jig isattached to the end face polishing device for optical fiber ferrule(Embodiment 1).

FIG. 19 is a front view showing a state in which the polishing jig isnot attached to the end face polishing device for optical fiber ferrule(Embodiment 1).

FIG. 20 is a plan view partly showing a state of attaching the polishingjig (Embodiment 1).

FIG. 21 is a graph showing variations in radius of the optical fiberferrule end face relating to the polishing results of SC connector.

FIG. 22 is a graph showing variations in a deviation amount between anapex and the center point of the optical fiber ferrule relating to thepolishing results of SC connector (Embodiment 1).

FIG. 23 is a graph showing variations in a protrusion amount of theoptical fiber from the optical fiber ferrule relating to the polishingresults of SC connector (Embodiment 1).

FIG. 24 is a graph showing variations in an angle in X-direction of theend face of optical fiber ferrule relating to the polishing results ofMT ferrule (Embodiment 1).

FIG. 25 is a graph showing variations in an angle in Y-direction of theangle of the optical fiber ferrule end face relating to the polishingresults of MT ferrule (Embodiment 1).

FIG. 26 is a graph showing variations in radius in X-direction in aflatness of the end face of the optical fiber ferrule relating to thepolishing results of MT ferrule (Embodiment 1).

FIG. 27 is a graph showing variations in radius in Y-direction in aflatness of the end face of the optical fiber ferrule relating to thepolishing results of MT ferrule (Embodiment 1).

FIG. 28A is a conceptual cross-sectional view partly showing the opticalfiber ferrule before the end face is polished

FIG. 28B is a conceptual plan view showing a state of independentlypolishing the optical ferrule before the end face is polished.

FIG. 29 is a cross-sectional view schematically and partly showing avariation of a load cell arrangement with respect to the pressing forcetransmission mechanism (Embodiment 1).

FIG. 30A is a schematic cross-sectional view of the cam portion and acam drive portion (Embodiment 1).

FIG. 30B is a schematic cross-sectional view of the cam portion(Embodiment 1).

FIG. 30C is a schematic cross-sectional view of the cam portion(Embodiment 1).

FIG. 31 is a cross-sectional perspective view schematically and partlyshowing the end face polishing device for optical fiber ferrule(Embodiment 2).

FIG. 32 is a side view schematically showing a part (holding portionguiding support part and pressing force transmission mechanism) of theend face polishing device for optical fiber ferrule, shown partially incross-section (Embodiment 3).

FIG. 33 is a plan view schematically and partly showing the end facepolishing device for optical fiber ferrule (Embodiment 4).

FIG. 34 is a cross-sectional view schematically and partly showing theend face polishing device for optical fiber ferrule taken along aXXXIV-XXXIV line shown in FIG. 33 (Embodiment 4).

FIG. 35 is a side view schematically and partly showing the end facepolishing device for optical fiber ferrule (Embodiment 4).

FIG. 36 is a conceptual diagram of a locked linkage in an application tothe polishing plate (Embodiment 5).

FIG. 37 is a conceptual diagram of a wedge plate and its surroundingstructure used for the locked linkage (Embodiment 5).

FIG. 38 is a conceptual diagram of the wedge plate and its surroundingstructure used for the locked linkage in an application to the post(Embodiment 5).

MODES FOR CARRYING OUT THE INVENTION

The purposes of the present invention are to polish the end face of theoptical fiber ferrule by use of an adjusted polishing pressure and toimprove a polishing accuracy. The purposes are achieved as follows.

Invention of Claim 1

In the invention of claim 1, an end face polishing device for opticalfiber ferrule for polishing an end face of an optical fiber ferrule byapplying a polishing pressure between a polishing plate driven by apolishing drive shaft and an optical fiber ferrule held by a holdingportion, the end face polishing device for optical fiber ferrulecomprising: a bearing portion for allowing the polishing plate to rotaterelatively around the polishing drive shaft and to move relatively tothe polishing drive shaft in an axial direction; a polishing plate guidesupporting portion movable only in an axial movement direction of thepolishing plate for movably supporting the polishing plate on a baseportion to apply the polishing pressure to the holding portion byallowing the polishing plate to move in the axial direction; a pressingdrive source for adjustably outputting a driving force to apply thepolishing pressure; and a pressing force transmission mechanism fortransmitting the driving force output from the pressing drive source asa pressing force in the axial movement direction of the polishing platevia the polishing plate guide supporting portion.

Invention of Claim 2

In the invention of claim 2, an end face polishing device for opticalfiber ferrule for polishing an end face of an optical fiber ferrule byapplying a polishing pressure between a polishing plate driven by apolishing drive shaft and an optical fiber ferrule held by a holdingportion, the end face polishing device for optical fiber ferrulecomprising: a bearing portion for allowing the polishing plate to rotaterelatively around the polishing drive shaft and to move relatively tothe polishing drive shaft in an axial direction; a polishing plate guidesupporting portion for movably supporting the polishing plate on a baseportion to apply the polishing pressure to the holding portion byallowing the polishing plate to move in the axial direction; a pressingdrive source for adjustably outputting a driving force to apply thepolishing pressure; and a pressing force transmission mechanism fortransmitting the driving force output from the pressing drive source asa pressing force in an axial movement direction of the polishing platevia the polishing plate guide supporting portion, wherein a drive sourceto rotate the polishing drive shaft is fixed on the base portion.

Invention of Claim 3

In the invention of claim 3, the end face polishing device for opticalfiber ferrule according to claim 1 or 2, wherein the polishing driveshaft includes a revolution drive shaft fitted in a center portion ofthe polishing plate to make the polishing plate revolve while allowing aself-rotation of the polishing plate, and the bearing portion allows thepolishing plate to rotate relatively around the revolution drive shaftand to move relatively to the revolution drive shaft in the axialdirection.

Invention of Claim 4

In the invention of claim 4, the end face polishing device for opticalfiber ferrule according to any one of claims 1 to 3, wherein thepolishing plate guide supporting portion has a thrust ring and an axialmovement guide, the thrust ring supports an outer peripheral portion ofa bottom surface of the polishing plate by a plane surface to serve as apart of the pressing force transmission mechanism for transmitting thepressing force while allowing the polishing plate to be driven, and theaxial movement guide is joined to the thrust ring at one end of theaxial movement guide and movably supported by the base portion to serveas a part of the pressing force transmission mechanism for transmittingthe pressing force from the other end of the axial movement guide.

Invention of Claim 5

In the invention of claim 5, the end face polishing device for opticalfiber ferrule according to claim 4, wherein the pressing forcetransmission mechanism includes a direct motion mechanism and a cammechanism, the direct motion mechanism being supported by the baseportion, the direct motion mechanism includes: a direct motion memberwhich performs a linear movement in a direction crossing the axialmovement direction by the transmitted pressing force; and a linearmotion guide for supporting the direct motion member on the base portionto allow the linear movement, and the cam mechanism performs a camaction to convert and transmit a force generated by the linear movementof the direct motion member to a pressing force in the axial movementdirection.

Invention of Claim 6

In the invention of claim 6, the end face polishing device for opticalfiber ferrule according to claim 5, wherein the cam mechanism includes acam portion and a cam drive portion which perform the cam action, thecam portion includes an inclined surface provided in a cam structure,the cam structure is joined to the other end of the axial movement guideto convert and transmit the force generated by the linear movement ofthe direct motion member, and the cam drive portion is supported by thedirect motion member and abutted with the inclined surface to transmitthe force generated by the linear movement of the direct motion memberto the inclined surface.

Invention of Claim 7

In the invention of claim 7, the end face polishing device for opticalfiber ferrule according to any one of claims 1 to 3, wherein thepolishing plate guide supporting portion has a thrust ring and a guidering, the thrust ring supports an outer peripheral portion of a bottomsurface of the polishing plate by a plane surface to serve as a part ofthe pressing force transmission mechanism for transmit the pressingforce while allowing the polishing plate to be driven, the guide ringmovably supports the thrust ring on the base portion to transmit thepressing force in the axial movement direction, the pressing forcetransmission mechanism has a driving ring on the base portion, thedriving ring being arranged at a bottom part of the thrust ring so as tobe opposed to the thrust ring, the driving ring being driven by thedriving force to rotate around a rotational shaft extending along theaxial movement direction, and the thrust ring has an end face camprovided between the thrust ring and the driving ring to make the thrustring move in the axial movement direction for transmitting the pressingforce when the driving ring rotates.

Invention of Claim 8

In the invention of claim 8, an end face polishing device for opticalfiber ferrule for polishing an end face of an optical fiber ferrule byapplying a polishing pressure between a polishing plate driven by apolishing drive shaft and an optical fiber ferrule held by a holdingportion, comprising: a holding portion guiding support part for movablysupporting the holding portion on a base portion to apply the polishingpressure to the polishing plate by allowing the holding portion to movein an axial direction; a pressing drive source for adjustably outputtinga driving force to apply the polishing pressure; and a pressing forcetransmission mechanism for transmitting the driving force output fromthe pressing drive source as a pressing force in an axial movementdirection of the holding portion, wherein the holding portion guidingsupport part has axial movement guides, one end side of each of theaxial movement guides is joined to a post for attaching a polishing jigused for fixing the optical fiber ferrule, and each of the axialmovement guides is movably supported by the base portion to serve as apart of the pressing force transmission mechanism for transmitting thepressing force from the other end.

Invention of Claim 9

In the invention of claim 9, the end face polishing device for opticalfiber ferrule according to claim 8, wherein the pressing forcetransmission mechanism includes a direct motion mechanism and a cammechanism, the direct motion mechanism being supported by the baseportion, the direct motion mechanism includes: a direct motion memberwhich performs a linear movement in a direction crossing the axialmovement direction by the transmitted pressing force; and a linearmotion guide for supporting the direct motion member on the base portionto allow the linear movement; and the cam mechanism performs a camaction to convert and transmit a force generated by the linear movementof the direct motion member to a pressing force in the axial movementdirection.

Invention of Claim 10

In the invention of claim 10, the end face polishing device for opticalfiber ferrule according to claim 9, wherein the cam mechanism includes acam portion and a cam drive portion which perform the cam action, thecam portion includes an inclined surface provided in a cam structure,the cam structure is joined to the other end of the axial movement guideto convert and transmit the force generated by the linear movement ofthe direct motion member, and the cam drive portion is supported by thedirect motion member and abutted with the inclined surface to transmitthe force generated by the linear movement of the direct motion memberto the inclined surface.

Invention of Claim 11

In the invention of claim 11, the end face polishing device for opticalfiber ferrule according to claim 4 or 8, wherein the pressing forcetransmission mechanism includes a wedge mechanism which performs a wedgeeffect for transmitting a force generated by a linear movement as thepressing force in the axial movement direction.

Invention of Claim 12

In the invention of claim 12, the end face polishing device for opticalfiber ferrule according to any one of claims 4, 8, and 11, wherein thepressing force transmission mechanism has a pressing bottom member on alower side of the base portion for transmitting the pressing force inthe axial movement direction, the pressing bottom member has a flatupward coupling face which extends in a front-and-back direction of thelinear movement so as to cross the axial movement direction, and theaxial movement guides are fixed directly or indirectly to the upwardcoupling face.

Invention of Claim 13

In the invention of claim 13, the end face polishing device for opticalfiber ferrule according to claim 12, wherein the pressing forcetransmission mechanism has a pressing upper member on an upper side ofthe base portion for transmitting the pressing force in the axialmovement direction, the pressing upper member has a downward couplingface which extends in the front-and-back direction of the linearmovement, the axial movement guides are fixed directly or indirectly tothe downward coupling face, and the pressing bottom member, the axialmovement guides and the pressing upper member form a locked linkage.

Invention of Claim 14

In the invention of claim 14, the end face polishing device for opticalfiber ferrule according to any one of claims 1 to 13, wherein thepressing drive source is a pressing drive motor or an air cylinder.

Invention of Claim 15

In the invention of claim 15, the end face polishing device for opticalfiber ferrule according to any one of claims 1 to 4 and 8, wherein, thepressing drive source is an air cylinder, and the pressing forcetransmission mechanism transmits the pressing force so that an outputdirection of the air cylinder coincides with the axial movementdirection.

Invention of Claim 16

In the invention of claim 16, the end face polishing device for opticalfiber ferrule according to any one of claims 1 to 15, furthercomprising: a sensor provided in the pressing force transmissionmechanism, the sensor detecting the polishing pressure directly orindirectly, a controller for controlling the pressing drive source toadjust the polishing pressure detected by the sensor to a predeterminedpolishing pressure.

Other Configuration 1

The end face polishing device for optical fiber ferrule according toclaim 6, wherein it is possible to adopt a following configuration. Twocam portions and two cam drive portions are provided and the camportions are separately arranged on left and right sides with respect tothe front-and-back direction of the linear movement so that the camstructure is formed into a frame shape. Two or more axial movementguides are separately arranged on the left and right sides and the frontand back sides in the front-and-back direction. The direct motion memberhas two arm portions separately arranged on the outside of the left andright side of the cam structure. The cam drive portions are supported ondifferent arm portions to abut with an inclined surface of different camportions. The cam drive portions are abutted with the inclined surfacebetween the axial movement guides which are arranged in thefront-and-back direction of the linear movement.

Other Configuration 2

The end face polishing device for optical fiber ferrule according to theabove-described configuration 1, wherein it is possible to adopt aconfiguration that the axial movement guides are arranged in a balancedmanner in the circumferential direction of the thrust ring.

Other Configuration 3

The end face polishing device for optical fiber ferrule according to theabove-described configuration 2, wherein it is possible to adopt aconfiguration that the cam drive portions are abutted with the inclinedsurface in the center position between the axial movement guides whichare arranged in the front-and-back direction of the linear movement.

Other Configuration 4

The end face polishing device for optical fiber ferrule according to anyone of the above-described configurations 1 to 3, wherein it is possibleto adopt a following configuration. The polishing plate is driven forpolishing by revolution and self-rotation of the polishing drive shaftby a revolution motor and a self-rotation motor, the revolution motorand the self-rotation motor are arranged inside the frame shape of thecam structure, and the revolution motor and the self-rotation motor arearranged in the front-and-back direction of the linear movement.

Embodiment 1 Schematic External Appearance of End Face Polishing Device

FIG. 1 is a perspective view partly showing an end face polishing deviceof optical fiber ferrule. FIG. 2 is a side view partly showing the endface polishing device for optical fiber ferrule. FIG. 3 is a perspectiveview partly showing a bottom surface of the end face polishing devicefor optical fiber ferrule seen from one side. FIG. 4 is a perspectiveview partly showing the bottom surface of the end face polishing devicefor optical fiber ferrule seen from the other side.

Hereinafter, terms of front, back, left and right define positions anddirections when the polishing device is seen from a front side, andterms of top and bottom define positions and directions when thepolishing plate of the polishing device is arranged to laid upward.

As shown in FIG. 1 to FIG. 4, the end face polishing device 1 foroptical fiber ferrule has a base plate 3 as a base portion. The baseplate 3 has a polishing plate 5 and posts 9 arranged on a top surfaceside.

The base plate 3 is a substrate for attaching components and has arectangle plate shape. However, the shape of the base plate 3 is notlimited to the rectangle plate. The shape of the base plate 3 can bechanged in accordance with the specification of the device. Thepolishing plate 5 has a polishing film and a polishing pad on its topsurface and driven for the polishing by a polishing drive shaft. Theposts 9 forms holding portions to hold optical fiber ferrules in thisembodiment as described below.

The end face polishing device 1 applies a polishing pressure between thepolishing plate 5 and the optical fiber ferrules held by the posts 9 topolish the end face of optical fiber ferrules using the polishing filmand the like provided on the polishing plate 5 which is driven for thepolishing.

The base plate 3 has a revolution motor 11 and a self-rotation motor 13on its bottom surface. The revolution motor 11 and the self-rotationmotor 13 serve as drive sources to drive for the polishing withrevolution and self-rotation.

The base plate 3 has a pressing drive motor 15 on the bottom surface ofthe base plate 3 to serve as a pressing drive source. The pressing drivemotor 15 adjustably outputs a driving force to apply polishing pressure.

The pressing drive motor 15 may be a stepping motor or a servomotor tocontrol position and load. Alternatively, the pressing drive motor 15may be any pressing drive sources capable of adjusting output. Any othermotors may be used depending on the specification of the device.Examples of the pressing drive source may include an air drive and ahydrostatic drive. The air drive will be explained in details later.

The pressing drive motor 15 has a ball screw 19 on an output side, andthe ball screw 19 is connected via an interlocking mechanism 17 such asa timing gear and a timing belt so as to be interlocked with thepressing drive motor 15. The ball screw 19 forms a part of a pressingforce transmission mechanism 21. The pressing force transmissionmechanism 21 transmits a driving force output from the pressing drivemotor 15 as a pressing force in an axial movement direction of thepolishing plate 5.

When the pressing force is transmitted by the pressing forcetransmission mechanism 21, the polishing plate 5 is moved upward againstthe posts 9. This movement allows the polishing plate 5 to adjust andapply the pressing force to the optical fiber ferrules held by the posts9. Thus, the polishing pressure to polish the end face of the opticalfiber ferrules is adjusted.

The pressing drive motor 15, the revolution motor 11 and theself-rotation motor 13 are connected to a controller 22. The controller22 may be formed, for example, by a microcomputer which has MPU, ROM,and RAM and the like to control the pressing drive motor 15, therevolution motor 11 and the self-rotation motor 13.

The pressing drive motor 15 adjusts the polishing pressure by a feedbackcontrol as described below. The controller controls the number ofrotation and the direction of rotation for both the revolution motor 11and the self-rotation motor 13 using a preinstalled program to make thepolishing plate 5 revolve and to self-rotate.

Structure of Revolution and Self-rotation

FIG. 5 is a cross-sectional view schematically and partly showing theend face polishing device for optical fiber ferrule seen from a frontside. FIG. 6 is an enlarged cross-sectional view partly showing abearing portion between a revolution drive shaft and a polishing plate.FIG. 7 is a plan view showing a relationship between a revolution driveshaft and a self-rotation drive shaft. FIG. 8 is a cross-sectional viewschematically showing a variation of a bearing portion between arevolution drive shaft and a polishing plate.

As shown in FIG. 5, the polishing plate 5 in this embodiment is drivenby a polishing drive shaft for the polishing with revolution andself-rotation.

The polishing drive shaft includes a revolution drive shaft 23 which isfitted into the center portion of the polishing plate 5 to make thepolishing plate 5 revolve while allowing a self-rotation of thepolishing plate 5. In this embodiment, the revolution drive shaft 23 andthe self-rotation drive shaft 25 form the polishing drive shaft. The wayto drive the polishing plate 5 is not limited to the revolution and theself-rotation. The polishing drive shaft may be configured by either oneof the revolution drive shaft or the self-rotation drive shaft.

The polishing plate 5 is formed into a disc shape. The polishing plate 5has a flat thrust surface 5 a formed in the outer peripheral portion ofthe bottom surface of the polishing plate 5. The polishing plate 5 has aboss portion 5 b which is projected lower than the thrust surface 5 aand formed at the center portion of the bottom surface of the polishingplate 5. The polishing plate 5 has a bearing hole 5 c which is locatedat the center portion of the polishing plate 5 and opens toward thebottom surface of the boss portion 5 b. The polishing plate 5 has ashaft fitting hole 5 d which is located at the off-centered position andopens toward the bottom surface of the boss portion 5 b. The polishingplate 5 has a polishing pad 26 and a polishing film 27 attached to thetop surface of the polishing plate 5.

Bearing Portion

As shown in FIG. 5 and FIG. 6, the upper part of the revolution driveshaft 23 is fitted into the bearing hole 5 c of the polishing plate 5via a ball guide 29. The bearing hole 5 c and the ball guide 29 form abearing portion 30 which is provided between the revolution drive shaft23, which is the polishing drive shaft, and the polishing plate 5. Thebearing portion 30 allows the polishing plate 5 to rotate relativelyaround the shaft and to move relatively to the shaft in an axialdirection. Especially, the use of the ball guide 29 allows the polishingplate 5 to rotate relatively around the shaft and to move relatively tothe shaft in the axial direction between the revolution drive shaft 23and the polishing plate 5.

Examples of the bearing portion, which allows the polishing plate 5 torotate relatively around the shaft and to move relatively to the shaftin the axial direction, may include a ball bush, an oil-less bush andthe like other than the ball guide 29. Alternatively, other bearingportion may be used as long as the bearing portion allows the polishingplate 5 to rotate relatively around the shaft and to move relatively tothe shaft in the axial direction even if they do not positively allowthe polishing plate 5 to rotate relatively around the shaft and to moverelatively to the shaft in the axial direction.

Polishing Plate Guide Supporting Portion

As shown in FIG. 5, the outer peripheral portion on the bottom surfaceof the polishing plate 5 is supported by the base plate 3 via apolishing plate guide supporting portion 31. The polishing plate guidesupporting portion 31 is configured to apply the polishing pressurewhile allowing the polishing plate 5 to move in an axial movementdirection with respect to the posts 9, which are the holding portion.Consequently, the polishing plate guide supporting portion 31 movablysupports the polishing plate 5 on the base plate 3. The axial movementof the polishing plate 5 is a movement in a top-and-bottom direction(up-down direction) with respect to the base plate 3 and the post 9.

The polishing plate guide supporting portion 31 has a thrust ring 33 andan axial movement guide 35.

The thrust ring 33 serves as a part of the pressing force transmissionmechanism 21 for transmitting the pressing force while allowing thepolishing plate 5 to be driven for the polishing. Consequently, thethrust ring 33 supports the outer peripheral portion of the bottomsurface of the polishing plate 5 by a plane surface. The pressing forcetransmission mechanism 21 will be further described later.

The thrust ring 33 has a thrust receiving surface 33 b on a top surface33 a of the thrust ring 33. The thrust ring 33 has a flat downwardcoupling face 33 c on a bottom surface of the thrust ring 33. Thecoupling face 33 c is configured to extend along the front-and-backdirection of the later described linear movement.

The axial movement guide 35 is formed by a splined shaft, and two ormore splined shafts are disposed. Hereinafter, the axial movement guide35 is referred to as the splined shaft 35. In this embodiment, foursplined shafts 35 are disposed. However, it is possible to dispose atleast two splined shafts 35.

The splined shaft 35 is directly fixed to the downward coupling face 33c of the thrust ring 33. The splined shaft 35 is movably supported bythe base plate 3 and is guided in an axial movement direction of thepolishing plate 5. The splined shaft 35 is movably supported by the baseplate 3 with a spline bush. The spline bush will be described later.

The splined shaft 35 is joined to the thrust ring 33 at one end. Thepressing force is transmitted from the other end of the splined shaft 35in the axial movement direction of the polishing plate 5. That means thesplined shaft 35 functions as a part of the pressing force transmissionmechanism 21.

In other words, the thrust ring 33 a member to form a part of thepressing force transmission mechanism 21. The thrust ring 33 is arrangedabove the base plate 3 and has the flat downward coupling face 33 c,which extends along the front-and-back direction of the later describedlinear movement.

Therefore, the outer peripheral portion of the bottom surface of thepolishing plate 5 is supported on the thrust receiving surface 33 b ofthe thrust ring 33. When the splined shaft 35 receives a transmittedpressing force and the splined shaft 35 is moved upward from the baseplate 3, the polishing plate 5 is moved upward via the thrust ring 33 bythe transmitted pressing force. When the splined shaft 35 is moveddownward, the polishing plate 5 is also moved downward in conjunctionwith the splined shaft 35.

The splined shaft 35 is not necessarily fixedly joined to the thrustring 33, and the use of a simple joining is possible. In the case ofusing the simple joining, the thrust ring 33 is energized down towardthe base plate 3 by a spring and the like. The splined shaft 35 may beformed by a general shaft or the like.

In addition, the splined shaft 35 does not necessarily function as apart of the pressing force transmission mechanism 21, and it is possibleto transmit the pressing force to the thrust ring 33 by a pressing rodthat is separately provided on the base plate 3.

Structure of Revolution and Self-rotation

The revolution drive shaft 23 is arranged so that its shaft centerextends along a top-and-bottom direction of the end face polishingdevice 1. The top-and-bottom direction of the end face polishing device1 is a vertical direction when the end face polishing device 1 is placedhorizontally. In this case, the shaft center of the revolution driveshaft 23 is arranged along the vertical direction.

The revolution drive shaft 23 is arranged next to the revolution outputshaft 37. The bottom part of the revolution drive shaft 23 is connectedto the upper part of the revolution output shaft 37 with a connectionmember 39. A fitting interval between the connection member 39 and therevolution output shaft 37 is fixed with a locking screw, an adhesivematerial or the like (not illustrated). Therefore, the revolution outputshaft 37 cannot be rotated relatively to the connection member 39. Inthis embodiment, a fitting interval between the connection member 39 andthe revolution drive shaft 23 is also fixed with a locking screw, anadhesive material or the like (not illustrated). Therefore, therevolution drive shaft 23 cannot be rotated relatively to the connectionmember 39.

Note that it is possible to use the ball guide 29 between the connectionmember 39 and revolution drive shaft 23 instead of using the ball guide29 between the polishing plate 5 and revolution drive shaft 23. Further,it is possible to adopt a support structure with a ball bearing ineither one of fitting intervals between the revolution drive shaft 23and the polishing plate 5 or between the revolution drive shaft 23 andthe connection member 39 while adopting a support structure with theball guide 29 or the like in the other fitting interval.

The revolution output shaft 37 is an output shaft of the revolutionmotor 11. Therefore, when the revolution motor 11 starts, the revolutionoutput shaft 37 is rotated. This rotation is transmitted to therevolution drive shaft 23 via the connection member 39. Since therotation is transmitted, the revolution drive shaft 23 is integrallyrevolved around the shaft center of the revolution output shaft 37.

The base plate 3 has a shaft insertion hole 41 that is concentricallyformed around the revolution output shaft 37 so as to penetrate the baseplate 3 from the bottom surface. The shaft insertion hole 41 has alarger diameter than the external diameter of the revolution outputshaft 37, and a gap is formed between the shaft insertion hole 41 andthe revolution output shaft 37. The revolution output shaft 37penetrates the shaft insertion hole 41 and projects upward.

Inside the base plate 3, a shaft support hole 43 which communicates withthe upper part of the shaft insertion hole 41 is concentrically formedwith a larger diameter than the shaft insertion hole 41. Further, inupper part of the base plate 3 in its thickness direction, aself-rotation gear accommodation hole 45 which communicates with theupper part of the shaft support hole 43 is concentrically formed with alarger diameter than the shaft support hole 43. The self-rotation gearaccommodation hole 45 penetrates to the top surface of the base plate 3.The self-rotation gear accommodation hole 45 has a gear mounting portion45 a at the bottom.

In the self-rotation gear accommodation hole 45, a self-rotation drivegear 47 is rotatably accommodated. The self-rotation drive gear 47 has aboss portion 47 a which projects downward in a center portion of thebottom surface of the rotation drive gear 47. The self-rotation drivegear 47 has a large-diameter hole 47 b in the center part of therotation drive gear 47. The bottom surface of the outer peripheralportion of the self-rotation drive gear 47 is mounted on the gearmounting portion 45 a formed in the self-rotation gear accommodationhole 45, and the boss portion 47 a fits into the shaft support hole 43.A gap is formed between the boss portion 47 a and the bottom portion ofthe shaft support hole 43. Since the self-rotation drive gear 47 isaccommodated as described above, the self-rotation drive gear 47 can besmoothly rotated relatively in the self-rotation gear accommodation hole45.

In the large-diameter hole 47 b formed in the self-rotation drive gear47, the revolution drive shaft 23 and the connection member 39 aremovably disposed together with the revolution output shaft 37.

On the top surface of the self-rotation drive gear 47, a secondconnection member 49 is fixed with a pin 51. The self-rotation driveshaft 25 is fixed to the second connection member 49. The self-rotationdrive shaft 25 is disposed on the outer diameter side of theself-rotation drive gear 47 with respect to the pin 51. Theself-rotation drive shaft 25 is fitted to the shaft fitting hole 5 d ofthe polishing plate 5. This fitting enables the self-rotation driveshaft 25 and the shaft fitting hole 5 d to rotate relative to each otheraround the shaft and move relative to each other in the axial direction.It is also possible to enable the relative rotation around the shaft andthe relative movement in the axial direction by inserting a bush or thelike between the self-rotation drive shaft 25 and the shaft fitting hole5 d. Examples of the bush may include a ball bush and an oil-less bush.

It is also possible to enable the relative rotation around the shaft andthe relative movement in the axial direction between the self-rotationdrive shaft 25 and the second connection member 49 by fixing theself-rotation drive shaft 25 to the shaft fitting hole 5 d. It is alsopossible to enable the relative rotation around the shaft and therelative movement in the axial direction by adopting a support structurewith a ball bearing in either one of fitting intervals between theself-rotation drive shaft 25 and the shaft fitting hole 5 d or betweenthe self-rotation drive shaft 25 and the second connection member 49.

As shown in FIG. 5 and FIG. 7, the revolution drive shaft 23 is revolvedaround the revolution output shaft 37 along a track T1. If therevolution output shaft 37 is stopped relatively, the self-rotationdrive shaft 25 is rotated around the revolution drive shaft 23 along thetrack T2.

With this structure, when the revolution motor 11 starts, the revolutionoutput shaft 37 is rotated. This rotation force is transmitted to therevolution drive shaft 23 via the connection member 39, and therevolution drive shaft 23 integrally revolves around the shaft center ofthe revolution output shaft 37.

At the same time, when the self-rotation motor 13 starts, theself-rotation drive gear 47 is interlockingly rotated and theself-rotation drive shaft 25 is rotated via the pin 51 and the secondconnection member 49.

Due to the above described revolution and self-rotation movements drivenby the revolution motor 11 and the self-rotation motor 13, the polishingplate 5 is self-rotated while being revolved around the revolutionoutput shaft 37. Accordingly, the polishing plate 5 is driven for thepolishing with revolution and self-rotation. Due to the driving for thepolishing with revolution and self-rotation, the polishing plate 5exhibits a hypotrochoid motion, for example.

In such a case, a self-rotation frequency is about 0.5 to 1.2 withrespect to a revolution frequency of 100, for example. However, theself-rotation frequency and the revolution frequency may be freely setdepending on the specification of the device.

The driving of the polishing plate 5 for the polishing is not limited tothe hypotrochoid motion as long as the polishing plate 5 can polish theend face of the optical fiber ferrule held by the post 9. Therefore, thepolishing plate 5 may exhibit any other motions including an epitrochoidmotion. Similarly, the driving of the polishing plate 5 for thepolishing is not limited to the self-revolution and the rotation. Thedriving for the polishing may be only one of the revolution or theself-rotation. Further, the driving of the polishing plate 5 for thepolishing may be a linear movement in the front-and-back direction.

It is also possible to configure a variation of the bearing portion 30as shown in FIG. 8. In FIG. 5, the polishing plate 5 has the bossportion 5 b formed on the bottom surface of the polishing plate 5. Onthe other hand, in the variation shown in FIG. 8, a connecting bossportion 53 is fixed to the flat bottom surface of the polishing plate 5by welding, adhesion or the like. The connecting boss portion 53 has abearing hole 53 a which penetrates the connecting boss portion 53 andcommunicates with the bearing hole 5 c. The connecting boss portion 53is concentrically formed so that the connecting boss portion 53 has thesame diameter as the bearing hole 5 c. The ball guide 29 between thepolishing plate 5 and the revolution drive shaft 23 is mainly supportedby the bearing hole 53 a.

In this variation, the polishing plate 5 can be formed thinner and thisrealizes the weight reduction of the polishing plate 5.

Pressing Force Transmission Mechanism

FIG. 9 is a side view schematically showing a part (polishing plateguide supporting portion and pressing force transmission mechanism) ofthe end face polishing device for optical fiber ferrule, shown partiallyin cross-section. FIG. 10 is a bottom view schematically showing a part(pressing force transmission mechanism) of the end face polishing devicefor optical fiber ferrule, shown partially in cross-section. FIG. 11 isan explanatory view showing a lifted state and a layout of the pressingforce transmission mechanism. FIG. 12 is a conceptual diagram showing alocked linkage of a cam structure, axial movement guide, and a thrustring. FIG. 13 is an explanatory view showing a layout of the pressingforce transmission mechanism.

As shown in FIG. 9 to FIG. 13, the pressing force transmission mechanism21 is configured to adjust the polishing pressure. Consequently, thepressing force transmission mechanism 21 transmits the driving forcethat is output from the pressing drive motor 15 to the polishing plate 5as a pressing force in the axial movement direction of the polishingplate 5.

The pressing force transmission mechanism 21 is housed in a housing 55of the device to which the base plate 3 is mounted. The pressing forcetransmission mechanism 21 includes a direct motion mechanism 57 and acam mechanism 59. The direct motion mechanism 57 is supported by thebase plate 3.

Direct Motion Mechanism

The direct motion mechanism 57 includes a direct motion member 61 and alinear motion guide 63.

The direct motion member 61 performs a linear movement in a directioncrossing the axial movement direction of the polishing plate 5 by thetransmitted pressing force. A front-and-back direction of the linearmovement is aligned with the front-and-back direction of the end facepolishing device 1. However, the front-and-back direction of the linearmovement may be aligned to the left and right direction of the end facepolishing device 1 depending on the specification of the end facepolishing device 1.

The direct motion member 61 has a pair of arm portions 61 a, 61 b, and abase portion 61 c. The arm portions 61 a, 61 b are formed integrallywith the base portion 61 c on the left and right ends of the baseportion 61 c so that the arm portions 61 a, 61 b extend along thefront-and-back direction of the linear movement. The arm portions 61 a,61 b respectively have cam follower support portions 61 aa, 61 ba at thetip of each arm portion, and each cam follower support portion isprojected downward. The cam follower support portions 61 aa, 61 ba arearranged to face each other so that they are separated on the outer leftside and the outer right side of the later-described cam structure.

The linear motion guide 63 is configured to support the direct motionmember 61 on the base plate 3 to allow the linear movement of the directmotion member 61. That means the linear motion guide 63 supports thedirect motion member 61 on the base plate 3 and allows the linearmovement of the direct motion member 61. The linear motion guide 63 maybe formed by a ball spline, a ball bush, a linear bush, a cross roller,a linear guide, or the like. In this embodiment, the linear motion guide63 is configured by a linear guide and the linear guide has guide rails63 a and blocks 63 b. The guide rails 63 a are fixed to the bottomsurface of the base plate 3.

The guide rails 63 a extend along the front-and-back direction of thearm portions 61 a, 61 b so that the left and the right guide rails 63 aare parallelly positioned.

The blocks 63 b are formed by a hard ball, a holder or the like. Twoblocks 63 b are provided for each guide rail 63 a. However, the numberof the blocks 63 b is not limited to two and any numbers of the blocks63 b is possible. The blocks 63 b provided for each guide rail 63 a isattached to each of the left and right arm portions 61 a, 61 b. Inrespective arm portions 61 a, 61 b, one of the blocks 63 b is arrangedon the top end of respective cam follower support portions 61 aa, 61 baand the other is arranged on the base portion 61 c side. With thisarrangement of the blocks 63 b, the moment of each arm portion 61 a, 61b generated by a cam action of the cam mechanism 59 is surelytransmitted to the guide rails 63 a side by the pair of blocks 63 b.

Therefore, the direct motion member 61 surely makes the cam mechanism 59to perform the cam action while performing the linear movement in thefront-and-back direction by using the linear motion guide 63.

The pressing drive motor 15 is arranged behind the direct motionmechanism 57 with an interval. The pressing drive motor 15 is fixed to afixing bracket 67. The fixing bracket 67 is formed into a plate shapeand arranged so that the plate surfaces are oriented to thefront-and-back direction. The top end of the fixing bracket 67 is fixedto the bottom surface of the base plate 3 so that the fixing bracket 67is hung down vertically.

A moving bracket 69 is arranged between the fixing bracket 67 and thedirect motion mechanism 57. The moving bracket 69 is formed into a plateshape. The moving bracket 69 is arranged parallel to the fixing bracket67 so that the plate surfaces of the moving bracket 69 are oriented tothe front-and-back direction. The bottom end side of the moving bracket69 is moveably guided by a bracket guide 71. Therefore, the movingbracket 69 can move forward and backward along the bracket guide 71between the fixing bracket 67 and the direct motion mechanism 57.

The moving bracket 69 has a nut 73 attached above the bracket guide 71and positioned in the center portion of the bracket guide 71 in the leftand right direction. A ball screw 19 is screwed to the nut 73. The ballscrew 19 penetrates the fixing bracket 67 with being loosely engaged,and the ball screw 19 is connected to the pressing drive motor 15.

Therefore, when the pressing drive motor 15 starts and rotates, the ballscrew 19 is rotated. The moving bracket 69 is moved linearly via the nut73 between the fixing bracket 67 and the direct motion mechanism 57.

The joining structure between the pressing drive motor 15 and the movingbracket 69 shown in FIG. 9 and FIG. 10 is slightly different from theconnection structure shown in FIG. 1 to FIG. 4 in that a timing belt orthe like is used in FIG. 1 to FIG. 4. In a schematic configuration shownin FIG. 9 and FIG. 10, the ball screw 19 is directly joined to thepressing drive motor 15. Anyway, a common concept is same as theconnection structure of FIG. 1 to FIG. 4 in a point that the rotationforce from the pressing drive motor 15 makes the moving bracket 69 movelinearly via the ball screw 19. This concept is simplified and shown inFIG. 9, FIG. 10.

The upper part of the moving bracket 69 is interlocked with the side ofthe base portion 61 c of the direct motion member 61 so that the movingbracket 69 can move forward and backward relatively within apredetermined range. In the upper part of the moving bracket 69, a loadcell overload protection mechanism 75 is attached. The front edge of theload cell overload protection mechanism 75 abuts with a load cell 77.The load cell 77 is arranged at the back end face of the base portion 61c of the direct motion member 61.

Therefore, when the moving bracket 69 is moved forward, the load celloverload protection mechanism 75 is integrally moved forward. With thismovement, the load cell overload protection mechanism 75 presses theload cell 77 to transmit the pressing force to the direct motion member61. The load cell 77 detects the pressing force transmitted to thedirect motion member 61. The detection signal detected by the load cell77 is input to the controller 22.

In this embodiment, the load cell 77 is provided in the pressing forcetransmission mechanism 21 and serves as a sensor for indirectlydetecting the polishing pressure between the polishing plate 5 and theoptical fiber ferrule held by the post 9.

The controller 22 calculates the polishing pressure between thepolishing plate 5 and the end face of the optical fiber ferrule by usingthe input signal. The controller 22 is configured to feedback controlthe pressing drive motor 15 so that the polishing pressure detected fromthe calculation becomes a predetermined polishing pressure. This controlallows the end face of the optical fiber ferrule to be polished with thepredetermined polishing pressure.

The direct motion member 61 is moved along the guide rails 63 a by thetransmitted pressing force. When the direct motion member 61 is movedalong the guide rails 63 a, the blocks 63 b of the direct motion member61 is guided and moved by the guide rails 63 a.

Cam Mechanism

As shown in FIG. 9 and FIG. 10, the cam mechanism 59 performs a camaction to convert and transmit the linear movement of the direct motionmember 61 to the direction of the axial movement of the polishing plate5. The axial movement direction corresponds to a top-and-bottomdirection in figures.

The cam mechanism 59 includes a cam portion 79 and a cam drive portion81 which performs the cam action.

The cam portion 79 has inclined surfaces 79 a, 79 b that are provided ina cam structure 83. The cam structure 83 is connected to the bottom end(the other end) of the splined shaft 35 in this embodiment, and the camstructure 83 performs the cam action to convert and transmit thepressing force.

Cam followers 81 a, 81 b of the cam drive portions 81 are supported bythe direct motion member 61 and abut with the inclined surfaces 79 a, 79b. The cam followers 81 a, 81 b transmit the force produced by thelinear movement of the cam drive portion 81 interlocked with the directmotion member 61 to the inclined surfaces 79 a, 79 b. This transmissioncauses the cam action.

The inclined surfaces 79 a, 79 b of the cam portion 79 and the camfollowers 81 a, 81 b of the cam drive portion 81 are provided on bothleft and right sides forming a pair on each side.

The cam structure 83 is formed into a frame shape. A pair of inclinedsurfaces 79 a, 79 b are arranged on both left and right sides of the camstructure 83 with respect to the front-and-back direction of the linearmovement direction of the direct motion member 61. In this embodiment,the cam structure 83 has left and right portions 83 a, 83 b and frontand back portions 83 c, 83 d. These portions are integrally formed intoa rectangle frame shape in a planar view. The left and right portions 83a, 83 b are arranged in parallel to each other, and extends in thefront-and-back direction. As described above, the inclined surfaces 79a, 79 b are formed on the left and right portions 83 a, 83 b. The frontand back portions 83 c, 83 d are arranged in parallel to each other, andextends in the left and right direction.

The cam structure 83 is arranged so that the intersection of thediagonals of the rectangular outline corresponds to the center of thecircular outline of the thrust ring 33 as seen from a plan view. Withthis arrangement, the left and right portions 83 a, 83 b of the camstructure 83 are positioned on the inside of the left and right armportions 61 a, 61 b of the direct motion member 61. Therefore, the leftand right arm portions 61 a, 61 b are positioned on the left and rightoutside of the cam structure 83. The cam follower support portions 61aa, 61 ba of the left and right arm portions 61 a, 61 b are arranged toface each other and positioned on the left and right outside of the camstructure 83 while forming a small gap at the inside of respective leftand right portions 83 a, 83 b.

The inclined surfaces 79 a, 79 b of the cam portions 79 are located inan intermediate location in the vertical direction of respective leftand light portions 83 a, 83 b of the cam structure 83. The inclinedsurfaces 79 a, 79 b are arranged and set in respective openings 85 a, 85b which are formed into a long hole so as to incline downwardly towardthe front along the left and right portions 83 a, 83 b. The inclinedsurfaces 79 a, 79 b are disposed in parallel so as to be opposed eachother, and the inclined surfaces 79 a, 79 b incline downwardly towardthe front along the inclination of openings 85 a, 85 b. Therefore, inthis embodiment, the cam portion 79 is formed into a frame cam shapehaving the upper and lower inclined surfaces 79 a, 79 b in respectiveopenings 85 a, 85 b.

The cam drive portion 81 is formed by a pair of cam followers 81 a, 81b. The cam followers 81 a, 81 b are formed by rollers. The cam followers81 a, 81 b are respectively provided to the left and right arm portions61 a, 61 b, and respectively supported on the support cam followersupport portions 61 aa, 61 ba by pins 87 so as to be rotatable. Thediameter of the roller which forms respective cam followers 81 a, 81 bis approximately the same as the vertical interval between the inclinedsurfaces 79 a and 79 b. Since the diameter is set as such, the camfollowers 81 a, 81 b are capable of rolling between the inclinedsurfaces 79 a and 79 b.

Generally, the cam follower indicates a follower. However, in thisembodiment, the cam follower is used as a driving member instead of thefollower. In this case, the cam portion 79 serves as the follower. Thecam drive portion 81 may be anything which drives the cam portion 79 toperform a cam action by conversion and transmission. Consequently, thepresent invention may include variants other than the concept of the camfollower described in this embodiment. The variants may not necessarilyinclude the cam action, and any other mode that does not include the cammechanism may be used. These variants will be described later.

In response to the linear movement of the direct motion member 61 towardthe front, the cam followers 81 a, 81 b respectively push up upperinclined surfaces 79 a in each opening 85 a, 85 b while rolling towardthe front. In response to the linear movement of the direct motionmember 61 toward the back, followers 81 a and 81 b respectively pushdown the lower inclined surfaces 79 b in each opening 85 a, 85 b whilerolling toward the back.

That is, the force produced by the linear movement of the direct motionmember 61 in the front-and-back direction is converted to the pressingforce in the top-and-bottom direction and transmitted to the axialmovement of the polishing plate 5. Thus, the cam action is performed.This cam action enables the cam structure 83 to be moved and adjusted inthe top-and-bottom direction.

Abutment of Cam Follower Between Splined Shafts

As shown in FIG. 9 to FIG. 11, the upper part of the cam structure 83has a flat coupling face 89 which is laid upward and extending along thefront-and-back direction of the linear movement of the direct motionmember 61.

The above-described four splined shafts 35 are joined and fixed to thecoupling face 89 which is laid-upward. The flat bottom face of thesplined shaft 35 is abutted and joined to the coupling face 89 andfastened by a bolt 91.

The splined shaft 35 and the cam structure 83 are not necessarily fixed.The spline shaft 35 may be configured to be simply abutted with the camstructure 83. When the splined shaft is simply abutted, the splinedshaft 35 is preferably energized downward from the base plate 3 byspring and the like as described above.

The splined shaft 35 is joined to the cam structure 83 so that foursplined shafts 35 are arranged symmetrically in the left and rightdirection and the front-and-back direction of the linear movementdirection. The four splined shafts 35 are arranged in each corner sideof the coupling face 89 of the cam structure 83 as shown in a plane viewof FIG. 10.

In the arrangement of the splined shafts 35 with respect to the camstructure 83, the pair of cam followers 81 a, 81 b and the inclinedsurfaces 79 a, 79 b abut with each other at a position between thesplined shafts 35 disposed in the front-and-back direction of the linearmovement of the direct motion member 61.

In FIG. 11, the illustration on the left shows the cam structure 83before it is lifted, and the illustration on the right shows the camstructure 83 after it is lifted.

As shown in FIG. 11, the abutment of the pair of cam followers 81 a, 81b with inclined surfaces 79 a, 79 b is maintained at any positionsbetween the splined shafts 35 disposed in the front-and-back directionof the linear movement of the direct motion member 61.

Therefore, with the cam action performed by the cam mechanism 59, theforce produced by the linear movement of the direct motion member 61 isconverted to the pressing force in the top-and-bottom direction and theforce is surely transmitted to the four splined shafts 35.

Thrust Ring Input Balance

As shown in FIG. 9 to FIG. 13, the four splined shafts 35 penetratevertically through guiding holes 3 a of the base plate 3. At the lowerend face portion of the guiding holes 3 a, a spline bush 93 is attachedto each splined shaft 35. The splined shaft 35 penetrating through theguiding hole 3 a is fitted to the spline bush 93. The spline bush 93smoothly guides the splined shaft 35 along the vertical pressing forcetransmission direction.

The splined shafts 35 are joined and fixed to the inside of thering-formed flat coupling face 33 c of the thrust ring 33 so that foursplined shafts 35 are positioned with equal intervals of 90 degrees in acircumferential direction. The splined shaft 35 is fixed in such a waythat the flat upper end of the splined shaft 35 is abutted with (incontact with) the coupling face 33 c and fastened by a bolt 95.

Therefore, the four splined shafts 35 are fixed in a balanced manner inthe circumferential direction of the thrust ring 33.

This balanced arrangement enables the pressing force transmitted by thesplined shaft 35 to act on the thrust ring 33 with good load balance.Therefore, the polishing plate 5 can be surely pushed upward with goodload balance by the thrust ring 33 while being supported by the planesurface of the thrust ring 33.

Maximum Load Balance Input

As shown in FIG. 11, while the four splined shafts 35 are arranged inthe balanced manner with respect to the thrust ring 33, the pair of camfollowers 81 a, 81 b is arranged in the center position between thesplined shafts 35 in the front-and-back direction of the linear movementof the direct motion member 61 to provide the maximum pressing forceagainst the polishing plate 5 by the cam action. In other words, thecenter position between the splined shafts 35 in the front-and-backdirection serves as a balance position to transmit the pressing force tothe thrust ring 33 via the splined shaft 35. Since this balance positionis aligned with the center position of the cam followers 81 a, 81 b, themaximum load can be transmitted.

According to the above-described configuration, the pressing force withthe maximum load in the axial movement direction transmitted from thecam follower 81 a, 81 b via the inclined surface 79 a is equallydistributed and transmitted from the flat coupling face 89 of the camstructure 83 to the four splined shafts 35.

The pressing force which is equally distributed and transmitted to thefour splined shafts 35 is distributed and transmitted from the foursplined shafts 35 to four equally placed positions on the outerperipheral portion of the thrust ring 33.

Locked Linkage

As described above, the bottom ends of the four splined shafts 35 areabutted and joined with the flat coupling face 89 of the cam structure83 and fastened and fixed with the bolt 91 as shown in FIG. 12 and FIG.13.

With such fixing of the splined shaft, the load can be transmitted fromthe coupling face 89 to the bottom end of the four splined shafts 35substantially under the same conditions.

Furthermore, the top ends of the four splined shafts 35 are abutted andconnected with the flat coupling face 33 c of the thrust ring 33 andfastened and fixed with the bolt 95.

With such fixing, the four splined shafts 35, the cam structure 83, andthe thrust ring 33 form a locked linkage. The locked linkage allows theload in the top-and-bottom direction received by the cam structure 83 tobe transmitted from the coupling face 89 to the polishing plate 5 withrigidity via the four splined shafts 35 and thrust ring 33.

In this case, the cam structure 83 serves as a pressing bottom member ofthe pressing force transmission mechanism 21 in this embodiment. Thatmeans, as described above, the pressing force transmission mechanism 21has the cam structure 83 for transmitting the pressing force in theaxial movement direction on the lower side of the base plate 3.

The thrust ring 33 serves as a pressing upper member of the pressingforce transmission mechanism 21 in this embodiment. That means, asdescribed above, the pressing force transmission mechanism 21 has thethrust ring 33 for transmitting the pressing force in the axial movementdirection on the upper side of the base plate 3.

The splined shaft 35 may be directly joined to the cam structure 83 andthrust ring 33 as described in this embodiment, and the splined shaft 35may be indirectly joined via other members. It is also possible to joina pressing bottom member and a pressing upper member, which are formedseparately from the cam structure 83 and the thrust ring 33, to thesplined shaft 35 to form the locked linkage, and join the pressingbottom member and the pressing upper member to the cam structure 83 andthe thrust ring 33 in the axial movement direction.

Arrangement of Revolution Motor and Self-rotation Motor

Although a revolution motor and a self-rotation motor are omitted inFIG. 9 and FIG. 10, they are illustrated in FIG. 1 to FIG. 4 and furtherin FIG. 11 and FIG. 13. The revolution motor 11 and the self-rotationmotor 13 are drive sources which drive the polishing plate 5 for thepolishing. The revolution motor 11 and the self-rotation motor 13 arefixed to the base plate 3 so as to be arranged in the front-and-backdirection of the linear movement of the direct motion member 61 insidethe rectangle frame of the cam structure 83.

The revolution motor 11 is relatively large and arranged at a positionnear the center portion of the base plate 3 as seen from the plan view.The self-rotation motor 13 which is relatively small is arranged on thefront side of the base plate 3 as seen from the plan view. Theself-rotation motor 13 and the revolution motor 11 are disposed evenlyin the left and right direction so that the center line of the thrustring 33 in the front-and-back direction aligns with the center of therotation motor 13 and the revolution motor 11.

Holding Portion and Polishing Jig

FIG. 14 is a front view of a polishing jig used in the end facepolishing device for optical fiber ferrule. FIG. 15A is an enlarged planview showing a state in which a pressing member of the polishing jig isin a locked position. FIG. 15B is a cross-sectional view showing a statein which the pressing member of the polishing jig is in the lockedposition. FIG. 16 is a plan view of the polishing jig. FIG. 17 is abottom view of the polishing jig. FIG. 18 is a plan view showing a statein which the polishing jig is attached to the end face polishing devicefor optical fiber ferrule. FIG. 19 is a front view showing a state inwhich the polishing jig is not attached to the end face polishing devicefor optical fiber ferrule. FIG. 20 is a plan view partly showing a stateof attaching the polishing jig.

Holding Portion

As shown in FIG. 1 to FIG. 4 and FIG. 9, four posts 9 are provided onthe base plate 3 around the polishing plate 5 to serve as a holdingportion of the optical fiber ferrule. The four posts 9 are arranged atequal intervals centering on the center of the thrust ring 33 so as toform four corners.

The post 9 has a base shaft 97, a lever support shaft 99, apressurization lever 101, a spring bearing 103, and a pressurizationspring 105 to hold the polishing jig.

The base shaft 97 has a fitting shaft portion 97 a which is formed intoa stepped shape at the bottom part of the base shaft 97 a. The baseshaft 97 also has a fitting cylindrical portion 97 b at the upper partof the base shaft 97 a. The fitting shaft portion 97 a of the base shaft97 is fitted and fixed to a fitting hole 3 b. The fitting holes 3 b areformed in the base plate 3 at the positions where the four posts 9 arelocated. Here, only single fitting hole 3 b and single post 9 are shownin the figure for the purpose of convenience of illustrations.

The bottom part of the lever support shaft 99 is fitted to the fittingcylindrical portion 97 b. The lever support shaft 99 is supported by thefitting cylindrical portion 97 b so that the lever support shaft 99 canrotate around the shaft and move in the axial direction. At the upperpart of the lever support shaft 99, a spring bearing hole 99 a isformed.

The intermediate portion of the lever support shaft 99 has apressurization lever 101 attached in the radial direction. Thepressurization lever 101 has a pressurization pin portion 101 a which isintegrally formed. The pressurization lever 101 is projected to one sideof the lever support shaft 99 in the radial direction, and thepressurization pin portion 101 a is projected to the other side of thelever support shaft 99.

The spring bearing 103 has a head 103 a in one end and a male screwportion 103 b in the other end. The spring bearing 103 is disposed inthe shaft center portion of the lever support shaft 99 so that thespring bearing 103 can move relatively to the lever support shaft 99 inthe axial direction. The head 103 a of the spring bearing 103 isarranged in the spring bearing hole 99 a. The male screw portion 103 bof the spring bearing 103 is screwed and fixed to the fitting shaftportion 97 a. A locking screw 104 is utilized to prevent the male screwportion 103 b to be loosened. The pressurization spring 105 is insertedbetween the head 103 a of the spring bearing 103 and the bottom portionof the spring bearing hole 99 a.

Therefore, when the pressurization lever 101 is grasped and rotatedaround the shaft, the lever support shaft 99 is rotated around the shaftcenter with respect to the fitting cylindrical portion 97 b of the baseshaft 97. This rotation allows the pressurization lever 101 to rotatearound the shaft and the pressurization pin portion 101 a is rotatedaround the shaft center of the lever support shaft 99.

When the pressurization lever 101 is grasped and pulled up upward in theshaft direction, the lever support shaft 99 is moved upward in the axialdirection against the biasing force of the pressurization spring 105with respect to the fitting cylindrical portion 97 b. This movementallows the pressurization lever 101 to be pulled up and thepressurization pin portion 101 a is moved upward in the axial direction.

Polishing Jig

FIG. 14 is a front view of a polishing jig used in the end facepolishing device for optical fiber ferrule. FIG. 15A is an enlarged planview showing a state in which a pressing member of the polishing jig isin a locked position. FIG. 15B is a cross-sectional view showing a statein which the pressing member of the polishing jig is in the lockedposition. FIG. 16 is a plan view of the polishing jig. FIG. 17 is abottom view of the polishing jig.

In this embodiment, a MT ferrule having a MT optical connector is used.However, a SC ferrule having a SC optical connector or the like may besimilarly used. The MT ferrule is an optical fiber ferrule in whichseveral optical fibers (not illustrated) are bundled into a tape form(i.e., optical fiber tape) and is inserted into a ferrule. The SCferrule is an optical fiber ferrule in which one optical fiber isinserted into the ferrule. The MT ferrule has a rectangular crosssection and the SC ferrule has a circular cross section. Therefore, inthe case of using the SC ferrule, the polishing jig has a supportinsertion hole having a circular cross section.

As shown in FIG. 14 to FIG. 17, the polishing jig 107 has a holder plate109 to be attached to the end face polishing device 1, a pressing member111 and a rod member 113.

The holder plate 109 is a square plate as seen from a plan view. Theholder plate 109 has arc-shaped edges 110 formed at the four corners ofthe holder plate 109. The holder plate 109 has a screw hole 115 formedin a center portion of the holder plate 109.

The holder plate 109 has, for example, ten insertion holes 119 in theplane of the holder plate 109. In the insertion hole 119, the MTferrules 117 are inserted. The insertion holes 119 are arranged in acircumferential direction at equal intervals along the concentric circleof the screw hole 115 (FIG. 17) that is placed in a center portion ofthe plane. Each insertion hole 119 is formed into a rectangle shape inaccordance with the rectangular cross section of the MT ferrule 117.Each insertion hole 119 is configured to have a small gap between theinsertion hole 119 and the MT ferrule 117 when the MT ferrule 117 isinserted into the insertion hole 119. Each insertion hole 119 isarranged so that one side of the rectangle insertion hole 119 is alignedparallel to the tangent of the concentric circle.

The top surface of the holder plate 109 has a holding surface 121 aroundeach insertion hole 119. The holding surface 121 intersects the verticalinner wall of the insertion hole 119 at right angles. However, the innerwall of each insertion hole 119 is specified at a predetermined anglewith respect to the general surface (top surface) other than the holdingsurface 121 of the holding plate 109 so that the predetermined anglecorresponds to a polishing angle required for the end face of theoptical fiber ferrule. Of course, the insertion hole 119 may be formedvertically with respect to the general surface (top surface) of theholder plate 109 depending on the polishing angle.

The holder plate 109 has screw holes 123 arranged so as to correspond toeach insertion hole 119. A locking screw 125 is screwed into the screwhole 123 to mount the pressing member 111.

Each pressing member 111 has a long hole 127 penetrated in a centerportion of the pressing member 111. The locking screw 125 is insertedinto the long hole 127, and the locking screw 125 is screwed into thehole 123.

At the tip of each pressing member 111, a wall surface 129 and apressing surface 11 are formed. The wall surface 129 is formed to have aheight substantially equal to the height of the flange portion 117 a ofthe MT ferrule 117. The pressing surface 131 extends from the upper partof the wall surface 129 in substantially parallel with the holdingsurface 121.

When the locking screw 125 is loosen without releasing from the screwhole 123, the pressing member 111 can be slid outwardly with respect tothe insertion hole 119 by moving the pressing member 111 relatively tothe locking screw 125 via the long hole 127. This slide movement makesthe pressing surface 131 leave from the region around the insertion hole119, and the pressing member 111 stays in a standby position. When thepressing member is in the standby position, the MT ferrule 117 can beinserted and removed with respect to the insertion hole 119.

The MT ferrule 117 can be fixed in such a way that the MT ferrule 117 isinserted into the insertion hole 119 and then the pressing member 111 isslid until the wall surface 129 of the pressing member 111 lightlypushes the flange portion 117 a of the MT ferrule 117. When the pressingmember 111 is slid, the pressing surface 131 is positioned on the flangeportion 117 a of the MT ferrule 117. While maintaining this state, thelocking screw 125 is fastened with a predetermined force using a torquewrench or the like. The fastening makes the pressing surface 131 pressthe top surface of the flange portion 117 a of the MT ferrule 117downward with a predetermined force. Due to the fastening, the bottomsurface of the flange portion 117 a of the MT ferrule 117 is held withbeing closely contact with the holding surface 121.

The rod member 113 has a screw portion 135 (FIG. 17) at the bottom end,a knob 137 at the top end, and a cable hook 139 at the intermediateportion.

The screw portion 135 of the rod member 113 is screwed into the screwhole 115 of the holder plate 109. With this screw-in, the rod member 113is removably attached to the center of the holder plate 109.

The knob 137 of the rod member 113 is formed so as to be grasped by anoperator with one hand.

The cable hook 139 of the rod member 113 locks an optical fiber tape 141connected to the MT ferrule 117 placed on the holder plate 109. Thecable hook 139 is formed by a plate material having a disc shape, forexample. Hook portions 143 having a curved shape are formed around theouter periphery of the cable hook 139 so that one end of each hookportion 143 is connected to the cable hook 139. The cable hook 139 hastwelve hook portions 143, for example. The optical fiber tapes 141connected to each MT ferrule 117 are respectively locked to the hookportions 143. This enables all the optical fiber tapes 141 connected tothe MT ferrules 117 to be bundled and attached to the polishing jig 107.

Holding of Optical Fiber Ferrule

FIG. 18 is a plan view showing a state in which the polishing jig isattached to the end face polishing device for optical fiber ferrule.FIG. 19 is a front view showing a state in which the polishing jig isnot attached to the end face polishing device for optical fiber ferrule.FIG. 20 is a plan view partly showing a state of attaching the polishingjig.

As shown in FIG. 18 and FIG. 19, the polishing jig 107 is attached tothe end face polishing device 1.

As shown in FIG. 20, when the polishing jig 107 is attached, the fourpressurization levers 101 are turned so that all the pressurizing pins101 a are directed outside (shown by a chain line in the figure). Theedges 110 of the holder plate 109 (FIG. 16) are placed on the fittingcylindrical portions 97 b of four posts 9 to arrange the polishing jig107 on the end face polishing device 1. Then each pressurization lever101 is turned while being pulled up so that pressurizing pins 101 a areset to push down the four corners of the holder plate 109 (shown by asolid line in the figure). Therefore, in this embodiment, a part of theflat ring-formed surface provided on the top end of the fittingcylindrical portion 97 b serves as a jig-mounted portion. However, thejig-mounted portion may be arranged next to the post 9 separate from thefitting cylindrical portion 97 b.

When the polishing jig 107 is positioned and fixed to the four posts 9of the end face polishing device 1 as described above, the tip of the MTferrule 117 which is projected from the bottom surface of the polishingjig 107 is opposed to a polishing film 27 (FIG. 5).

Polishing

As shown in FIG. 14 to FIG. 20, the polishing jig 107 holding several MTferrules 117 is positioned and fixed to the four posts 9 of the end facepolishing device 1.

As shown in FIG. 1 to FIG. 5, FIG. 9 and FIG. 10, when a starting switchis turned on, the revolution motor 11 and the self-rotation motor 13 aredriven and controlled by revolution and self-rotation signals outputfrom the controller 22.

With the above described control, the revolution motor 11 and theself-rotation motor 13 are driven and controlled for the revolution andself-rotation. With the above described driving, the polishing plate 5is driven on the thrust ring 33 for the polishing to exhibit ahypotrochoid motion, for example.

On the other hand, the pressing drive motor 15 (FIG. 2, FIG. 9 and FIG.10) is driven and controlled by a pressing drive signal output from thecontroller 22 (FIG. 2).

With the above described driving, the ball screw 19 is rotated and themoving bracket 69 is moved linearly between the fixing bracket 67 andthe direct motion mechanism 57 via the nut 73, as described above. Withthe above described linear movement, the load cell overload protectionmechanism 75 presses the load cell 77 to transmit the pressing force tothe direct motion member 61. The load cell 77 detects the pressing forcetransmitted to the direct motion member 61. The above describeddetection signal is input to the controller 22.

The direct motion member 61 performs the linear motion toward the frontalong the guide rails 63 a of the linear motion guide 63 by thetransmitted pressing force.

When the direct motion member 61 is moved linearly toward the front, thecam followers 81 a, 81 b push up the upper inclined surfaces 79 a whilethe cam followers 81 a, 81 b are rolling, as described above. When thedirect motion member 61 is moved linearly toward the back, the camfollowers 81 a, 81 b push down the inclined surfaces 79 b while the camfollowers 81 a, 81 b are rolling, as described above.

That means, as described above, the cam action of the cam mechanism 59is performed such that the force produced by the linear movement of thedirect motion member 61 in the front-and-back direction is converted tothe pressing force in the top-and-bottom direction and transmitted tothe axial movement of the polishing plate 5.

When the inclined surfaces 79 a are pushed upward by the cam followers81 a, 81 b, the cam structure 83 is pushed upward and the splined shaft35 is lifted while being guided by the spline bush 93 to transmit thepressing force to the thrust ring 33.

With the above described transmission of the pressing force, the thrustring 33 is moved upward to lift the polishing plate 5.

When the polishing plate 5 is lifted, the polishing film 27 of thepolishing plate 5 is pressed against the tip of the MT ferrule 117 frombelow. With the above described pressing, the polishing pressure isapplied so that the polishing film 27 is pressed in by 0.1 mm, forexample.

In this case, the detection signal of the pressing force detected by theload cell 77 is input to the controller 22, and the controller 22calculates the current polishing pressure from the detection signal, asdescribed above. Based on the above described calculation, the pressingdrive motor 15 is feedback controlled so that the current polishingpressure becomes equal to the predetermined polishing pressure stored inthe controller 22. As a result, it is possible to maintain and adjustthe polishing pressure.

Effect of Embodiment 1

The end face polishing device 1 for optical fiber ferrule in Embodiment1 of the present invention has: the bearing portion 30 including theball guide 29; the polishing plate guide supporting portion 31 includingthe thrust ring 33 and the splined shaft 35; the pressing drive motor15; and the pressing force transmission mechanism 21 including thedirect motion mechanism 57 and the cam mechanism 59.

The bearing portion 30 is configured to allow the polishing plate 5 torotate relatively around the shaft and move relatively in the axialdirection between the revolution drive shaft 23 and the polishing plate5. The polishing plate guide supporting portion 31 is configured tomovably support the polishing plate 5 on the base plate 3 to apply thepolishing pressure while allowing the polishing plate 5 to move withrespect to the posts 9. The pressing drive motor 15 is configured toadjustably output the driving force to apply polishing pressure. Thepressing force transmission mechanism 21 is configured to transmit thedriving force output from the pressing drive motor 15 to the axialmovement direction of the polishing plate 5 as the pressing force.

Therefore, the polishing plate 5 can be moved in the axial directionwith respect to the posts 9 by the drive force output from the pressingdrive motor 15 while the polishing plate 5 is driven for the polishingwith the revolution and the self-rotation.

At this time, the axial movement against the base plate 3 can be surelyachieved by the thrust ring 33 and the splined shaft 35.

In addition, the revolving polishing plate 5 which is driven by therevolution drive shaft 23 is allowed to rotate relatively around theshaft and move relatively in the and axial direction by use of the ballguide 29 at the time of the axial movement against the posts 9.

Accordingly, the polishing plate 5 can apply the pressing force to theMT ferrule 117 held by the posts 9 from below while the polishing plate5 is driven for the polishing. Thus, it is possible to precisely adjustthe polishing pressure between the polishing plate 5 and the MT ferrule117 to accurately polish the end of the MT ferrule 117.

Since the polishing pressure is adjusted by the axial movement of thepolishing plate 5 in the top-and-bottom direction, the end of the MTferrule 117 can also be polished while the polishing jig 107 iscompletely or strongly fixed and held in the posts 9 by omitting thepressurization spring 105 of the posts 9 or by setting the repulsiveforce of the pressurization spring 105 strong.

By polishing the end face while the polishing jig is held by beingcompletely fixed as described above, it is possible to realize otherpolishing methods which have not conventionally been made. The polishingmethods will be described later.

Further, the pressing drive motor 15 to drive the polishing plate 5, thedirect motion mechanism 57, the cam mechanism 59 and the like can beaccommodated in the housing 55 located underneath. This makes the upperside of the polishing plate 5 open.

Consequently, it is also possible to place the end face polishing device1 in a production line and automatically provide and place the polishingjig 107 supporting the MT ferrule 117 on the end face polishing device 1from upward in the production line. Thus, an automation can be realized.

The thrust ring 33 is configured to support the outer peripheral portionof the bottom surface of the polishing plate 5 by a plane surface toserve as a part of the pressing force transmission mechanism 21 fortransmitting the pressing force while allowing the polishing plate 5 tobe driven for the polishing. The splined shaft 35 is configured to beconnected to the thrust ring 33 at one end and movably supported by thebase plate 3 via the ball guide 29 on the other end to serve as a partof the pressing force transmission mechanism 21 for transmitting thepressing force in the axial movement direction.

Therefore, when the splined shaft 35 receives the transmitted pressingforce as a part of the pressing force transmission mechanism 21, thesplined shaft 35 is smoothly moved upward in the axial direction withrespect to the base plate 3 to lift the thrust ring 33.

Consequently, the polishing plate 5, which is driven for the polishingwhile being revolved and self-rotated on the thrust ring 33, can belifted by the adjusted pressing force.

The polishing pressure between the polishing plate 5 and the MT ferrule117 can be precisely adjusted by the pressing force, and the end of theMT ferrule 117 can be accurately polished.

The direct motion mechanism 57 is configured to have: the direct motionmember 61 which performs the linear movement in a direction crossing theaxial movement direction by the transmitted pressing force; and thelinear motion guide 63 which supports the direct motion member 61 on thebase plate 3 to allow the linear motion. The cam mechanism 59 isconfigured to perform the cam action so that the linear movement forceof the direct motion member 61 is transmitted in the axial movementdirection as the pressing force.

Therefore, when the direct motion member 61 is driven by the drivingforce output from the pressing drive motor 15, the cam mechanism 59transmits the force produced by the linear movement of the direct motionmember 61 in the axial movement direction of the polishing plate 5 asthe pressing force.

Accordingly, the polishing pressure between the polishing plate 5 andthe MT ferrule 117 can be precisely adjusted by driving the pressingdrive motor 15. Thus, the end of the MT ferrule 117 can be accuratelypolished.

The cam mechanism 59 is configured to have: the cam portion 79 whichperforms the cam action; and cam followers 81 a, 81 b which serve as thecam drive portion 81. The cam portion 79 is configured to have inclinedsurfaces 79 a, 79 b formed in the cam structure 83. The cam structure 83is configured to be connected to the other end of the splined shaft 35so as to convert and transmit the force as described above. The camfollowers 81 a, 81 b are configured to be supported by the direct motionmember 61 and abutted with the inclined surfaces 79 a, 79 b to transmitthe force produced by the linear movement of the direct motion member 61to the inclined surfaces 79 a, 79 b.

Therefore, the cam action is performed with the cam followers 81 a, 81 bbeing abutted with the inclined surfaces 79 a, 79 b. That means it ispossible to perform the cam action by so-called wedge effect.

Consequently, the driving force output from the pressing drive motor 15is transmitted to the polishing plate 5 after it is increased. Thus,large load can be obtained.

Further, since the above-described configuration can be realized bysmall components, the mechanism can be configured to be compact. Becauseof this, the pressing drive motor 15, the direct motion mechanism 57 andthe cam mechanism 59 can be easily accommodated in the housing 55 of thedevice and thus downsizing of the whole device can be achieved.

A pair of cam portions 79 and a pair of cam drive portions 81 areprovided. In the cam structure 83, the pair of cam portions 79 areseparately arranged on left and right sides with respect to thefront-and-back direction of the linear movement. Thus, the cam structure83 is formed into a flame shape. The splined shafts 35 are arrangedseparately on left and right sides and front and back sides in thefront-and-back direction. The direct motion member 61 has a pair of armportions 61 a, 61 b. Each of the arm portions 61 a, 61 b is separatelyarranged on the outside of the left and right sides of the cam structure83. The followers 81 a, 81 b are respectively supported by the armportions 61 a, 61 b so that cam followers 81 a, 81 b respectively abutwith the inclined surfaces 79 a, 79 b provided on the pair of the camportions 79. The cam followers 81 a, 81 b abut with the inclinedsurfaces 79 a, 79 b between the splined shafts 35 arranged in thefront-and-back direction of the linear movement.

Therefore, the driving force output from the pressing drive motor 15 isconverted and transmitted between the splined shafts 35. Thus, theconverted and transmitted pressing force is distributed to the foursplined shafts 35 and the distributed pressing force is surelytransmitted to the polishing plate 5.

The four splined shafts 35 are arranged in the same radius of the thrustring 33 at equal intervals in the circumferential direction in abalanced manner.

Therefore, the force converted and transmitted between the splinedshafts 35 is transmitted with good balance from the splined shafts 35 tothe polishing plate 5 as the pressing force.

The cam followers 81 a, 81 b are configured to abut with inclinedsurfaces 79 a, 79 b in the center position between the splined shafts 35which are arranged in the front-and-back direction of the linearmovement. The center position is determined on the premise that the foursplined shafts 35 are arranged in the circumferential direction of thethrust ring 33 in a balanced manner so as to be symmetrically arrangedboth in the front-and-back and the left-and-right directions.

The center position in such arrangement serves as a balance position ofthe pressing force when the pressing force is transmitted from thesplined shaft 35 to the thrust ring 33.

Therefore, the force that is converted and transmitted at the centerposition between the splined shafts 35 can be transmitted from thesplined shafts 35 to the polishing plate 5 as the pressing force withgood balance. That is, it is possible to transmit equal load from fourpoints. The center position serves as a maximum load position, and thepressing force applied to the polishing plate 5 can be surelytransmitted as the polishing pressure.

Consequently, the end of the MT ferrule 117 can be accurately polishedby precisely adjusting the polishing pressure between the polishingplate 5 and the MT ferrule 117 through the feedback control of thepressing drive motor 15.

The polishing plate 5 is driven for the polishing when the revolutiondrive shaft 23 and the self-rotation drive shaft 25 are revolved andself-rotated by the revolution motor 11 and the self-rotation motor 13.The revolution motor 11 and the self-rotation motor 13 are fixed to thebase plate and arranged inside the flame of the cam structure 83 in thefront-and-back direction of the linear movement.

Therefore, the revolution motor 11, the self-rotation motor 13, thedirect motion mechanism 57, the cam mechanism 59 and the like can bestored by efficiently utilizing the space.

Consequently, it is possible to reduce wasted space among the revolutionmotor 11, the self-rotation motor 13, the direct motion mechanism 57,the cam mechanism 59 and the like in the front-back, left-right, andup-down directions. This enables these components to be easilyaccommodated in the housing 55 and achieves a downsizing of the deviceas a whole.

The upper part of the cam structure 83 has a flat coupling face 89 whichis laid upward and extending along the front-and-back direction of thelinear movement. The four splined shafts 35 are fixed to the upwardcoupling face 89.

Therefore, when the pressing force converted and transmitted by the cammechanism 59 is transmitted from the cam structure 83 to the foursplined shafts 35, the pressing force can be equally distributed andtransmitted from the coupling face 89 of the cam structure 83 to thefour splined shafts 35.

Since the pressing force is equally distributed and transmitted, thepressing force can be surely transmitted via the four splined shafts 35to the outer peripheral portion of the thrust ring 33.

Moreover, when the flat ends of the four splined shafts 35 are bondedand fixed to the flat upward coupling face 89, they are prevented orsuppressed from being relatively shifted or wobbled.

Consequently, the pressing force converted and transmitted by the cammechanism 59 can be surely transmitted from the cam structure 83 to thefour splined shafts 35 in the top-and-bottom direction with goodbalance.

The thrust ring 33 has a flat downward coupling face 33 c which extendsalong the front-and-back direction of the linear movement. The foursplined shafts 35 are fixed to the downward coupling face 33 c. Becauseof this, the cam structure 83, the splined shaft 35 and the thrust ring33 are not moved relatively to form a locked linkage.

Therefore, when the pressing force converted and transmitted by the cammechanism 59 is transmitted from the cam structure 83 to the thrust ring33 via the four splined shafts 35, the pressing force is transmitted bythe locked linkage.

Consequently, the pressing force converted and transmitted by the cammechanism 59 can be surely transmitted from the cam structure 83 to thethrust ring 33 via the four splined shafts 35 in the top-and-bottomdirection with good balance.

Moreover, when the flat ends of the four splined shafts 35 are bondedand fixed to the flat upward coupling face 89, they are prevented orsuppressed from being relatively shifted or wobbled.

The end face polishing device 1 has: the load cell 77 which is providedon the direct motion member 61 of the pressing force transmissionmechanism 21 to indirectly detect the polishing pressure; and thecontroller 22 for controlling the pressing drive motor 15 to adjust thepolishing pressure to a predetermined polishing pressure.

Therefore, the polishing pressure between the polishing plate 5 and theMT ferrule 117 can be surely controlled through the feedback control ofthe pressing drive motor 15.

Consequently, the end of the MT ferrule 117 can be accurately polishedby precisely adjusting the polishing pressure.

The above described effects can also be obtained in the case of using aSC ferrule with SC connector.

Polishing Result

FIG. 21 to FIG. 27 are graphs of the evaluation of the polishing result.FIG. 21 is a graph showing variations in radius of the optical fiberferrule end face relating to the polishing results of SC connector. FIG.22 is a graph showing variations in a deviation amount between an apexand the center point of the optical fiber ferrule relating to thepolishing results of SC connector. FIG. 23 is a graph showing variationsin a protrusion amount of the optical fiber from the optical fiberferrule relating to the polishing results of SC connector. FIG. 24 is agraph showing variations in an angle in X-direction of the end face ofoptical fiber ferrule relating to the polishing results of MT ferrule.FIG. 25 is a graph showing variations in an angle in Y-direction of theangle of the optical fiber ferrule end face relating to the polishingresults of MT ferrule. FIG. 26 is a graph showing variations in radiusin X-direction in a flatness of the end face of the optical fiberferrule relating to the polishing results of MT ferrule. FIG. 27 is agraph showing variations in radius in Y-direction in a flatness of theend face of the optical fiber ferrule relating to the polishing resultsof MT ferrule.

FIG. 21 to FIG. 23 show polishing results in IPC mode, and FIG. 24 toFIG. 27 show polishing results in OPC mode.

Here, the IPC mode is a polishing method that the applicant has alreadydescribed in Japanese Unexamined Patent Application Publication No.2002-1641. In the IPC mode, a position accuracy is maintained with thepolishing plate being a reference position, and a spring is installed ina polishing holder which holds each optical fiber ferrule independently,and a polishing load is applied independently to each optical fiberferrule.

The OPC mode does not use the polishing plate as a reference position,and the polishing is controlled by a load applied from the polishingplate to the end face of the optical fiber ferrule. The OPC mode isdifferent from the above-described Patent Document in that the opticalfiber ferrule is polished while the optical fiber ferrule is completelyfixed to the polishing holder. Therefore, it is necessary to control theload by the polishing plate.

FIG. 21 to FIG. 23 show results of the polishing when twenty opticalfiber ferrules (SCPC) are held and polished (IPC 20-shaft-SCPC). FIG. 24to FIG. 27 show results of the polishing when twenty-four MT ferrulesdescribed above are fixed and polished (Fixed 24-shaft-MT).

The polishing conditions of IPC 20 shaft-SCPC and Fixed 24 shaft-MT areas shown in following Table 1 and Table 2, for example.

TABLE 1 IPC 20-shaft-SCPC Pres- Abrasive sure grain of per Numberpolishing Polishing each of Process film base ferule rotation Time Water1 Adhesive SiC Rubber 4 N 110 rpm 30 Distilled agent 15 μm plate secwater removal 2 Rough Diamond Rubber 4 N 110 rpm 60 Distilled polishing9 μm plate sec water 3 Intermediate Diamond Rubber 4 N 110 rpm 120Distilled polishing 1 μm plate sec water 4 Finishing SiO₂ Rubber 4 N 110rpm 60 Distilled polishing plate sec water

TABLE 2 Fixed 24-shaft-MT Polishing conditions Pres- Abrasive sure grainof per Number polishing Polishing each of Process film base ferulerotation Time Water 1 Adhesive SiC Glass 2N 110 rpm 30 Distilled agent15 μm plate sec water removal 2 Rough SiC Glass 2N 110 rpm 60 Distilledpolishing 5 μm plate sec water 3 Intermediate SiC Glass 2N 110 rpm 60Distilled polishing 3 μm plate sec water 4 Finishing SiC Glass 2N 110rpm 60 Distilled polishing 0.5 μm plate sec water 5 Final CeO Glass 2N110 rpm 120 Distilled polishing buffing plate sec water

As shown in FIG. 21 to FIG. 23, results of Radius, Apex and Fiber Heightwere within the required specifications.

Specifically, Radius in FIG. 21 means the radius of the end face of theferrule and the result was within the range of the requiredspecification of R10 to 25 mm. Apex of FIG. 22 means an apex offset,which is a deviation amount between the apex of the ferrule and thecenter of the fiber, and the result was within the range of the requiredspecification of 50 μm or less. Fiber Height of FIG. 23 means aprotrusion amount of the fiber protruded from the ferrule, and theresult was within the range of the required specification of 0 to 50 nm.

As shown in FIG. 24 to FIG. 27, the results of X angle, Y angle, Xradius minimum 2000 mm (X Radius min 2000 mm), Y radius minimum 5 mm (YRadius min 5 mm) were within the range of the required specifications.

Specifically, X angle of FIG. 24 means the angle of the end face of theferrule in an X-direction and the result was within the requiredspecification of ±0.15°. Y angle of FIG. 25 means the angle of the endface of the ferrule in a Y-direction and the result was within therequired specification of ±0.20°. X radius minimum 2000 mm (X Radius min2000 mm) of FIG. 26 means a flatness of the end face of the ferrule andthe result was within the required specification of radius 2000 mm ormore in the X-direction. Y radius minimum 5 mm (Y Radius min 5 mm) ofFIG. 27 means a flatness of the end face of the ferrule and the resultwas within the required specification of radius 5 mm or more inY-direction.

Extendibility of Polishing Method

FIG. 28A is a conceptual cross-sectional view partly showing the opticalfiber ferrule before the end face is polished. FIG. 28B is a conceptualplan view showing a state of independently polishing the optical ferrulebefore the end face is polished.

As shown in FIG. 28A, a removal portion 144 aa of an optical fiber 144 aand a removal portion 144 ba of an adhesive agent 144 b are exposed atthe end face of the optical fiber ferrule 144 before polishing.

Conventionally, the exposed removal portion 144 aa of the optical fiber144 a has been manually cut by an operator.

On the other hand, in a polishing method according to the embodiment ofthe present invention, the polishing jig 107 is fixed to the posts 9,and the polishing plate 5 is lifted from below while being revolved andself-rotated. Therefore, it is possible to polish and remove the removalportion 144 aa of the optical fiber 144 a which is supported by thepolishing jig 107.

As shown in FIG. 28B, when a single optical fiber ferrule 145 a ispolished, it has been necessary to dispose dummies 145 b, 145 c inaddition to the target optical fiber ferrule 145 a supported by thepolishing jig 147 in the conventional OPC mode polishing. The disposeddummies 145 b, 145 c served to regulate the polishing pressure so as notto make the polishing jig 147 be inclined.

On the other hand, in a polishing method according to the embodiment ofthe present invention, the polishing jig 107 is completely fixed to theposts 9, and it is possible to polish the optical fiber ferrule in a waythat the polishing plate 5 is lifted while the polishing plate 5 isrevolved and self-rotated. Therefore, it is unnecessary to dispose thedummies 145 b, 145 c, and the workability of the single ferrulepolishing is remarkably improved.

Direct Detection of Polishing Pressure

FIG. 29 is a cross-sectional view schematically and partly showing avariation of a load cell arrangement with respect to the pressing forcetransmission mechanism. The basic configuration is similar to that ofFIG. 9 and the like. Thus, the same reference numerals are denoted andthe overlapped explanations are omitted. With respect to theconfigurations and reference numerals which are not shown in FIG. 29,refer to FIG. 9 and the like.

In FIG. 9, the load cell 77 which serves as a sensor is attached to thedirect motion member 61. The detection at this position is an indirectdetection of the polishing pressure between the polishing plate 5 whichis driven for the polishing and the optical fiber ferrule held by theposts 9.

On the other hand, in the example of an end face polishing device 1A inFIG. 29, a pressing rod 149 which serves as a pressing forcetransmission mechanism 21A is included in addition to a polishing plateguide supporting portion 31A. In FIG. 29, a cam structure 83A of a cammechanism 59A is partially shown in a cam portion 79A, and conceptuallyillustrated in a wedge plate form.

The pressing rod 149 is arranged on the thrust ring 33 at equalintervals from the four splined shafts 35 of the polishing plate guidesupporting portion 31A in a circumferential direction. The pressing rod149 is connected to the bottom surface of the thrust ring 33. In thisvariation, the polishing plate guide supporting portion 31A does nottransmit the pressing force and does not form a part of the pressingforce transmission mechanism 21.

The number and the arrangement of the splined shafts 35 and the pressingrod 149 are not particularly limited as long as it is possible tosmoothly guide the polishing plate 5 in the axial movement direction andsmoothly transmit the pressing force.

The load cell 77A is fixed between the flat bottom end surface of thepressing rod 149 and the flat coupling face 89A of the cam structure83A. The flat top end of the pressing rod 149 is connected to thecoupling face 33 c of the thrust ring 33 and fixed by a bolt as in thecase of FIG. 9. The load cell 77A is connected to the controller 22shown in FIG. 2.

Therefore, the driving force output from the pressing drive motor asdescribed above is transmitted to the cam follower 81Aa, (81Ab). Then,the cam structure 83A is pressed upward by the cam action, and thepressing force is transmitted to the thrust ring 33 via the load cell77A and the pressing rods 149.

The thrust ring 33 is lifted by the transmitted pressing force, and thepolishing plate 5 is pushed and abutted with the end face of the opticalfiber ferrule. When the thrust ring 33 is lifted, the splined shafts 35are guided by the spline bushes 93 as described above. The splinedshafts 35 guide the polishing plate 5 to move in the axial movementdirection via the thrust ring 33 while the splined shaft 35 are guidedas described above. Thus, the splined shafts 35 transmit the pressingforce to the polishing plate 5. The polishing plate 5 is driven for thepolishing on the thrust ring 33 while receiving the transmitted pressingforce in the axial movement direction as described above.

The polishing pressure between the polishing plate 5 and the end face ofthe optical fiber ferrule held by the posts 9 is adjusted by thepressing force transmitted to the polishing plate 5. The polishingpressure is directly detected by the load cell 77A, and the signal isinput to the controller 22. The controller 22 feedback-controls thepressing drive motor 15 by using the above described input.

Therefore, in this variation, it is possible to feedback control thepressing drive motor 15 more directly by detecting the polishingpressure directly.

Variations of Cam Portion and Cam Drive Portion

FIG. 30A, FIG. 30B and FIG. 30C show variations. FIG. 30A is a schematiccross-sectional view of the cam portion and a cam drive portion. FIG.30B and FIG. 30C are schematic cross-sectional views of the cam portion.

FIG. 30A partially shows the cam structure 83B in the cam portion 79B,and the cam structure 83B is conceptually illustrated in a wedge plateform. The cam portion 79B has an inclined surface 79Ba (79Bb) formed ina single line shape. The reference numeral in the parenthesis indicateselements on the right side which is not illustrated. The same is appliedhereinafter.

The cam drive portion 81B of the cam mechanism 59B is a wedge plate 81Ba(81Bb) and has a single inclined surface 81Baa (81Bba). The inclinedsurface 81Baa (81Bba) is opposed to the inclined surface 79Ba (79Bb) ofthe cam portion 79B of the cam structure 83B.

Therefore, as in the case of the above cam follower 81 a (81 b), whenthe driving force output from the pressing drive motor is transmitted tothe wedge plate 81Ba (81Bb), the force produced by the linear movementby the direct motion member can be converted to the pressing force andtransmitted to the polishing plate 5 in the axial movement direction bythe cam action between the inclined surface 81Baa (81Bba) and theinclined surface 79Ba (79Bb). The similar operational effect as theabove described embodiment can be obtained.

FIG. 30B and FIG. 30C partially show cam structures 83C, 83D of a cammechanism 59C, 59D similar to FIG. 30A.

In the cam structure 83C in FIG. 30B, an inclined surface 79Ca (79Cb) ofthe cam portion 79C is formed by two inclined surfaces 79Caa (79Cab) and79Cba (79Cbb).

Therefore, the inclined surface 79Caa (79Cba) which has a relativelylarge inclined angle enables the cam structure 83C to move upwardrapidly, and the inclined surface 79Cab (79Cbb) which has a relativelysmall inclined angle enables the large pressing force to be transmittedby a slight movement.

With such a stepwise transmission of the pressing force, the pressingforce can be transmitted rapidly and accurately.

In a case of the cam portion 79C, the inclined surface 79Ca (79Cb) isformed by two inclined surfaces 79Caa (79Cab) and 79Cba (79Cbb).However, the inclined surface 79Ca (79Cb) may be configured to havethree or more inclined surfaces.

In the cam structure 83D in FIG. 30C, the inclined surface 79Da (79Db)of a cam portion 79D is formed into a curved surface.

With the curved inclined surface 79Da (79Db), the cam structure 83Denables a continuous transmission action in contrast to the stepwisetransmission action by the cam structure 83C in FIG. 30B.

Embodiment 2

FIG. 31 is a cross-sectional perspective view schematically and partlyshowing the end face polishing device for optical fiber ferrule inEmbodiment 2. The basic configuration is similar to Embodiment 1, andthe same reference numerals are denoted and the overlapped explanationsare omitted. With respect to the configurations and reference numeralswhich are not shown in FIG. 31, refer to FIG. 9 and the like explainedin Embodiment 1.

An end face polishing device 1E of FIG. 31 is configured to directlytransmit a rotational driving force to the thrust ring 33E as a pressingforce by the end face cam 151.

The polishing plate guide supporting portion 31E has the thrust ring 33Eand the guide ring 153.

The thrust ring 33E is configured to serve as a part of the pressingforce transmission mechanism 21E for transmitting the pressing forcewhile allowing the polishing plate 5 to be driven for the polishing asdescribed above. Consequently, the thrust ring 33E supports the outerperipheral portion of the bottom surface of the polishing plate 5 by aplane surface as described above. The concept of the support structureis the same as the above described embodiment.

The guide ring 153 has a ball retainer and movably supports the thrustring 33E on the base plate 3E. The support structure is different fromthe above described embodiment in its method, however, the concept issimilar to the above described embodiment in that the pressing force istransmitted in the axial movement direction.

Therefore, the thrust ring 33E is capable of moving in the axialmovement direction of the polishing plate 5 so as to transmit thepressing force to the polishing plate 5 arranged above the thrust ring33E while the thrust ring 33E is supported by the guide ring 153.

On the other hand, the pressing force transmission mechanism 21E in thisvariation has a driving ring 155.

The driving ring 155 is arranged at the bottom part of the thrust ring33E so as to be opposed to the thrust ring 33E. The driving ring 155 isconfigured to be driven to rotate around the rotational shaft extendingalong the axial movement direction of the polishing plate by the drivingforce output from the pressing drive motor which is a pressing drivesource.

The pressing drive motor is interlocked and bonded to the bottom part orthe like of the driving ring 155 by a gear, for example. Since thepressing drive motor is interlocked and bonded, the driving ring 155 canbe driven to rotate by the driving force output from the rotationaldrive pressing drive motor. The driving ring 155 is supported on thebase plate 3E by a bearing portion 157 and the driving ring 155 iscapable of rotating around the shaft.

The driving ring 155 has supporting rollers 159 supported by the drivingring 155. The supporting rollers 159 are supported at equal intervals inthe circumferential direction. The supporting rollers 159 support thebottom surface of the thrust ring 33E.

At the bottom surface of the thrust ring 33E, the end face cam 151 isprovided and the supporting rollers 159 abut with the end face cam 151.

Therefore, when the driving ring 155 is rotated by the driving forceoutput from the pressing drive motor, the circumferential position ofthe supporting roller 159 is changed with respect to the end face cam151 of the thrust ring 33E. The end face cam 151 performs the cam actionby the circumferential position of the supporting roller 159, and thethrust ring 33E transmits the pressing force in the axial movementdirection of the polishing plate.

With this transmission of the pressing force, the polishing plate ispressed, and the polishing pressure is applied between the polishingplate and end face of the optical fiber ferrule.

Therefore, also in this variation, the operational effect similar to theabove described Embodiment 1 can be obtained.

Furthermore, it is possible to transmit the driving force of thepressing drive motor directly to the thrust ring 33E. Therefore, asimple structure having a short transmission path and a smaller numberof parts can be realized.

It is also possible to form the end face cam on the driving ring 155 andsupport the supporting roller 159 on the thrust ring 33E side.

Alternatively, it is also possible to fix the driving ring 155 to thebase plate 3E, use the supporting rollers 159 as a plate cam, and forman inclined surface or a plane surface which abuts with thecircumferential surface of the plate cam on the bottom surface of thethrust ring 33E. The pressing drive motor and the plate cam can beinterlocked by engaging a gear ring which is driven to rotate by thepressing drive motor with a pinion gear attached to each shaft of theplate cam. It is also possible to attach a small sized pressing drivemotor to each rotational shaft of the plate cam.

Moreover, a pressurization plate may be fixed to the bottom end of thesplined shaft 35 instead of the cam structure of Embodiment 1. In such acase, an end face cam is formed on the bottom surface of thepressurization plate and the structures such as the driving ring 155 andthe supporting roller 159 are combined with the pressurization platehaving the end face cam.

Embodiment 3

FIG. 32 is a side view schematically showing a part (holding portionguiding support part and pressing force transmission mechanism) of theend face polishing device for optical fiber ferrule, shown partially incross-section in Embodiment 3. The basic configuration is similar tothat of Embodiment 1, and the same reference numerals are denoted andthe overlapped explanations are omitted.

In the end face polishing device 1F of the present embodiment, posts 9Fare operable in the top-and-bottom direction with respect to thepolishing plate 5 to adjust the polishing pressure.

Therefore, in the end face polishing device 1F of the presentembodiment, the thrust ring 33F is positioned on the base plate 3F so asnot to be able to change the position vertically.

The end face polishing device 1F of the present embodiment has a holdingportion guiding support part 161. The holding portion guiding supportpart 161 is configured to allow the posts 9F to move with respect to thepolishing plate 5 so as to apply the polishing pressure. Consequently,in the end face polishing device 1F, the posts 9F to which the holderplate 109 of the polishing jig 107 is attached are movably supported onthe base plate 3F. The basic structure of the posts 9F are similar tothat of Embodiment 1, and the end face polishing device 1F has aplurality of posts 9F, for example, four posts 9F.

In each of the posts 9F of the present embodiment, the holder plate 109of the polishing jig 107 is attached to an upper end portion of one endof the post 9F so that the post 9F serves as a part of the pressingforce transmission mechanism 21F to transmit the pressing force in theaxial movement direction of the post 9F from an axial movement guide 9Falocated at the other end.

In other words, at the bottom end portion of the post 9F, the axialmovement guide 9Fa is formed so as to extend straight downward. Theaxial movement guide 9Fa of the post 9F is formed integrally andcoaxially with the base shaft 97 so as to have the same diameter. Notethat the axial movement guide 9Fa may be formed thicker or thinner thanthe base shaft 97 as long as it is possible to move the post 9F in theaxial direction. Also, in the present embodiment, the axial movementguide 9Fa and the post 9F are joined by means of the integral formation.However, it is also possible to form the post 9F and the axial movementguide 9Fa separately and screw the post 9F in the axial movement guide9Fa for engage them. In case of the screwed engagement, thespecification of the device may be changed by selecting the length ofthe axial movement guide 9Fa.

In the axial movement guide 9Fa, the post 9F is supported in a fittinghole 3Fb of the base plate 3F via a ball bush 163. With the abovedescribed support, the axial movement guide 9Fa is configured to bemovably supported on the base plate 3F to transmit the pressing force.Since the axial movement guide 9Fa is movably supported, it is possibleto operate the post 9F vertically with respect to the polishing plate 5in the top-and-bottom direction. The other end of the post 9F, which isa flat end face of the axial movement guide 9Fa, is joined and fixed tothe upward coupling face 89 of a cam structure 83F in the housing 55.The fixing is made by a bolt as described in Embodiment 1.

Since the axial movement guide 9Fa is joined and fixed as such, it ispossible to transmit the force generated by the linear movement of thedirect motion member 61 in the axial movement direction of the post 9Fas the pressing force by the cam action of the cam mechanism 59.

At the upper part of the post 9F, the holder plate 109 of the polishingjig 107 is arranged as a member of the pressing force transmissionmechanism 21F. The holder plate 109 is positioned upper side of the baseplate 3F. As described above, the edge 110 of the holder plate 109 (FIG.16) is mounted on the flat upward coupling face provided on the fittingcylindrical portion 97 b of each of four posts 9F, and the edge 110 ofthe holder plate 109 is fixed by pressurization pin portion 101 a. Theholder plate 109 has the flat downward coupling face 109 a extendingalong the front-and-back direction of the linear movement of the directmotion member 61. With the coupling face 109 a, the holder plate 109 isfixed to the flat upward coupling face provided on the fittingcylindrical portion 97 b.

Due to the above described fixing, the axial movement guides 9Fa arestructured to be indirectly fixed to the downward coupling face 109 a ofthe holder plate 109 via the post 9F.

In the above described structure, when the pressurization spring 105 isset to be stronger, or the pressurization spring 105 is omitted and thelever support shaft 99 is completely fixed to the base shaft 97 to takea form of a complete fixing, the cam structure 83F, the axial movementguide 9Fa and the holder plate 109 are locked and form a linkage.

Note that the post 9F and the holder plate 109 are not fastened by abolt. Even in the above described case, when the pressing force istransmitted to the MT ferrule 117 via the holder plate 109, the holderplate 109 does not move relatively to the posts 9F. In this meaning, thelocked linkage is formed.

In the above described case, the cam structure 83F forms the pressingbottom member of the pressing force transmission mechanism 21F in thisembodiment. That is, the pressing force transmission mechanism 21F isconfigured to have the cam structure 83F on the lower side of the baseplate 3F to transmit the pressing force in the axial movement direction.

Also, the holder plate 109 forms the pressing upper member of thepressing force transmission mechanism 21F in this embodiment. In otherwords, the pressing force transmission mechanism 21F is configured tohave the holder plate 109 on the upper side of the base plate 3F totransmit the pressing force in the axial movement direction.

The axial movement guide 9Fa may be joined to the cam structure 83directly as described in the embodiment and the axial movement guide 9Famay also be joined indirectly via other members. Another configurationis possible in which a separate pressing bottom member other than thecam structure 83 is joined to the axial movement guide 9Fa to form alocked linkage, and these pressing bottom members are joined to the camstructure 83 in the axial movement direction.

The structure of the pressing force transmission mechanism 21F issimilar to that of Embodiment 1 within the range from the pressing drivemotor 15F to the cam structure 83F. Thus, the same reference numeralsare denoted to the direct motion mechanism 57 and the cam mechanism 59and the overlapped explanations are omitted. Various modifications maybe adopted in this embodiment as long as they are consistent withEmbodiment 1.

As described in Embodiment 1, when the driving force is output from thepressing drive motor 15F, the driving force is converted to the pressingforce and the pressing force is transmitted to the cam structure 83F viathe direct motion mechanism 57 and the cam mechanism 59 in thisembodiment.

In this embodiment, the cam followers 81 a, 81 b press down the inclinedsurfaces 79 b while the cam followers 81 a, 81 b are rolled toward thefront by the linear movement of the direct motion member 61. When thedirect motion member 61 is moved linearly toward the back, the camfollower 81 a (81 b) push up the inclined surfaces 79 a while the camfollower 81 a (81 b) are rolled.

Therefore, the polishing pressure is applied in such a way that the camstructure 83F is moved in the axial movement direction of the post 9F bythe cam action between the cam follower 81 a (81 b) and the lowerinclined surface 79 b, and the pressing force is transmitted while theaxial movement guide 9Fa of the post 9F is drawn downward.

Moreover, since the flat ends of four axial movement guides 9Fa arebonded and fixed to the flat upward coupling face 89, they are preventedor suppressed from being relatively shifted or wobbled.

Consequently, the pressing force which is converted and transmitted bythe cam mechanism 59 can be surely transmitted from the cam structure83F to the posts 9F in the top-and-bottom direction with good balancevia the four axial movement guide 9Fa.

Furthermore, due to the locked linkage formed through the cam structure83F, the axial movement guide 9Fa, and the holder plate 109, the loadreceived by the cam 83F in the top-and-bottom direction is transmittedfrom the coupling face 89 to the holder plate 109 with rigidity via thefour axial movement guide 9Fa and the post 9F.

Due to the transmission of the pressing force, the posts 9F are surelymoved downward.

When the posts 9F are moved downward, the tip of the MT ferrule 117supported by the polishing jig 107 is pressed from upward onto thepolishing film 27 of the polishing plate 5 which is positioned at apredetermined height. This pressing is similar to Embodiment 1, and apredetermined polishing pressure is applied so that the polishing film27 is pressed in by approximately 0.1 mm, for example.

In this case, as described in Embodiment 1, the detection signal of thepressing force detected by the load cell 77 is input to the controller22 (shown in FIG. 2), and the controller 22 calculates the currentpolishing pressure from the detection signal. Based on the abovedescribed calculation, the pressing drive motor 15F is feedbackcontrolled as described in Embodiment 1. As a result, the polishingpressure can be maintained and adjusted.

Therefore, in this embodiment, it is not necessary to movably supportthe thrust ring 33F. Thus, the structure can be simplified.

In addition, other operational effects similar to Embodiment 1 can beachieved.

In this embodiment, it is possible to provide a rod separately from thepost 9F to transmit the pressing force, and interlock and join thebottom end of rod to the cam structure 83F, and interlock and join thetop end side of the rod to the post 9F. In this case, the axial movementguide 9Fa of the post 9F is not interlocked and joined to the camstructure 83F so as to be freely moved. The rod serves as a part of thelocked linkage.

Embodiment 4

FIG. 33 to FIG. 35 relate to Embodiment 4. FIG. 33 is a plan viewschematically and partly showing the end face polishing device foroptical fiber ferrule. FIG. 34 is a cross-sectional view schematicallyand partly showing the end face polishing device for optical fiberferrule taken along a XXXIV-XXXIV line shown in FIG. 33. FIG. 35 is aside view schematically and partly showing the end face polishing devicefor the optical fiber ferrule. Note that the basic configuration issimilar to that of Embodiment 1, and the same reference numerals aredenoted and the overlapped explanations are omitted. With respect to theconfiguration and reference numerals not shown in FIG. 33 to FIG. 35,refer to FIG. 9 and the like of Embodiment 1.

As shown in FIG. 33 to FIG. 35, an end face polishing device 1G in thisembodiment has an air cylinder 15G as a pressing drive source. Thepressing force transmission mechanism 21G is configured to directlytransmit the pressing force by aligning the output direction of the aircylinder 15G with the axial movement direction of the polishing plate 5.Therefore, the direct motion mechanism 57 and the cam mechanism 59described in Embodiment 1 are omitted in the present embodiment.

The air cylinder 15G has a structure in which an internal-pressure iscontrolled by an electropneumatic regulator. The electropneumaticregulator calculates the polishing pressure from the internal-pressureand a piston diameter of the air cylinder 15G The electropneumaticregulator is connected to the controller 22G The controller 22G feedbackcontrols the electropneumatic regulator so that the polishing pressurecalculated by the electropneumatic regulator is adjusted to be thepredetermined the polishing pressure.

The air cylinder 15G is attached to the bottom surface of a cylindermounting plate 165. The cylinder mounting plate 165 is attached to thebottom surface of the base plate 3G by four columns 167, for example.

A piston rod 15Ga of the air cylinder 15G is joined to a pressurizationplate 169. The pressurization plate 169 is a part of the pressing forcetransmission mechanism 21G and the pressurization plate 169 is formedinto a circular shape as seen from a plan view, for example. Thepressurization plate 169 has flat coupling face 169 a on the topsurface. In the outer peripheral portion of the pressurization plate169, the coupling face 169 a is joined and fixed to the flat bottom endsurface of the splined shaft 35 by a bolt and the like. The joining bythe bolt is the same as Embodiment 1.

Similar to Embodiment 1, four splined shafts 35 are arranged at equalintervals on the outer peripheral portion of the thrust ring 33 in thecircumferential direction, for example. The shaft center of the pistonrod 15Ga is arranged to be aligned with the center of the thrust ring33. With the above described arrangement, the driving force from the aircylinder 15G is configured to be transmitted to the thrust ring 33evenly and in good balance.

As shown in FIG. 34 and FIG. 35, the bottom ends of the four splinedshafts 35 are abutted with the flat coupling face 169 a of thepressurization plate 169 and are fastened and fixed as described above.

It is similar to Embodiment 1 that a load transmission from the couplingface 169 a to the bottom ends of the four splined shafts 35 is achievedunder substantially the same conditions by the above described fixing.

Further, it is also the same as Embodiment 1 that the top ends of thefour splined shafts 35 and the flat coupling face 33 c of the thrustring 33 are fastened and fixed.

With the above described fixing, the four splined shafts 35, thepressurization plate 169, and the thrust ring 33 form a locked linkage.Due to the above described locked linkage, the load received by thepressurization plate 169 in the top-and-bottom direction can betransmitted from the coupling face 169 a to the polishing plate 5 withrigidity via the four splined shafts 35 and the thrust ring 33.

In this case, the pressurization plate 169 forms the pressing bottommember of the pressing force transmission mechanism 21G in thisembodiment. That means, as described above, the pressing forcetransmission mechanism 21G has the pressurization plate 169 on the lowerside of the base plate 3. The pressurization plate 169 transmits thepressing force in the axial movement direction.

The thrust ring 33 forms a pressing upper member of the pressing forcetransmission mechanism 21G in this embodiment. In other words, thepressing force transmission mechanism 21F is configured to have theholder plate 109 on the upper side of the base plate 3F to transmit thepressing force in the axial movement direction.

The splined shaft 35 may be directly joined to the pressurization plate169 and the thrust ring 33 as described in the embodiments, and thesplined shaft 35 may be indirectly joined via other members. It is alsopossible to join a pressing bottom member and a pressing upper member,which are formed separately from the pressurization plate 169 and thethrust ring 33, to the splined shaft 35 to form a locked linkage, andjoin the pressing bottom member and the pressing upper member to thepressurization plate 169 and the thrust ring 33 in the axial movementdirection.

Also, in this embodiment, similar to Embodiment 1, the splined shafts 35and the thrust ring 33 serve as a part of the pressing forcetransmission mechanism 21G in addition to serve as the polishing plateguide supporting portion 31.

In this embodiment, in response to the output from the air cylinder 15G,the piston rod 15Ga projects upward, and the driving force istransmitted to the pressurization plate 169.

The driving force transmitted to the pressurization plate 169 is equallytransmitted to the four splined shafts 35 as the pressing force. Thefour splined shafts 35 move upward against the base plate 3, and equallypress the outer peripheral portion of the thrust ring 33 at four points.

When the pressing force is transmitted to the thrust ring 33, thepolishing plate 5 is pushed upward, and the polishing pressure isapplied as in the case of Embodiment 1.

This polishing pressure is calculated by the electropneumatic regulator,and the controller 22G sends electric signals to the electropneumaticregulator so that the detected polishing pressure is adjusted to thepredetermined the polishing pressure. The electropneumatic regulatorcontrols the pressure of the air cylinder 15G to control the axialmovement of the piston rod 15Ga.

When the piston rod 15Ga is controlled to move downward, the polishingplate 5 is controlled to move downward by the converse movement of theabove described movement. Thus, the polishing pressure decreases ordisappears.

Accordingly, the polishing pressure is precisely controlled.

Therefore, in this embodiment, it is possible to omit the direct motionmechanism, the cam mechanism and the like. Thus, a compact device can berealized.

In addition, other operational effects similar to Embodiment 1 can beachieved.

Also, in this embodiment, it is possible to directly or indirectlydetect the polishing pressure by the load cell, and control theelectropneumatic regulator by the detection signals as in the case ofEmbodiment 1.

Alternatively, the pressing drive source may be replaced by the aircylinder in Embodiments 1 to 3. In this case, the air cylinder may behorizontally placed in accordance with the output direction.

Embodiment 5

FIG. 36 to FIG. 38 show a structure of using a wedge plate. FIG. 36 is aconceptual diagram of a locked linkage in an application to thepolishing plate. FIG. 37 is a conceptual diagram of a wedge plate andits surrounding structure used for the locked linkage. FIG. 38 is aconceptual diagram of the wedge plate and its surrounding structure usedfor the locked linkage showing in an application to the post. Note thatthe basic configuration is similar to that of Embodiment 1 or Embodiment3, and the same reference numerals are denoted and the overlappedexplanations are omitted. With respect to the configuration andreference numerals not shown in FIG. 36 to FIG. 38, refer to FIG. 9,FIG. 32 and the like of Embodiment 1 and Embodiment 3.

In the end face polishing device for optical fiber ferrule shown in FIG.36, the thrust ring 33 is included in the pressing force transmissionmechanism 21H.

As shown in FIG. 36, the pressing force transmission mechanism 21Hincludes a wedge mechanism 59H. The specific structure of the wedgemechanism 59H will be explained later in the description of FIG. 38.Here, the wedge mechanism 59H will be conceptually explained.

The wedge mechanism 59H includes first and second wedge plates 83H, 81H.The first and second wedge plates 83H, 81H convert a force produced by alinear movement to a pressing force and transmit the pressing force inthe axial movement direction of the polishing plate 5 by a wedge effect.The first and second wedge plates 83H, 81H are formed into a frameshape, for example, similar to the cam structure 83 in Embodiment 1.

The bottom end of the splined shaft 35, which is an axial movementguide, is joined and fixed to a flat coupling face 89H of the firstwedge plate 83H in a similar structure to Embodiment 1. The first wedgeplate 83H has a straight linear inclined surface 79Ha (79Hb) on left andright sides. The reference numeral in the parenthesis indicates elementson the right side which is not shown in the figure. The same is appliedhereinafter. The top end of the splined shaft 35 is joined and fixed tothe flat coupling face 33 c of the thrust ring 33 in a similar structureto Embodiment 1.

With the above described fixing, the four splined shafts 35, the firstwedge plate 83H, and the thrust ring 33 form a locked linkage. Due tothe above described locked linkage, the load received by the first wedgeplate 83H in the top-and-bottom direction can be transmitted from thecoupling face 89H to the polishing plate 5 with rigidity via the foursplined shafts 35 and thrust ring 33.

In this case, the first wedge plate 83H forms the pressing bottom memberof the pressing force transmission mechanism 21H in this embodiment.That means, as described above, the pressing force transmissionmechanism 21H has the first wedge plate 83H on the lower side of thebase plate 3 to transmit the pressing force in the axial movementdirection.

The thrust ring 33 forms a pressing upper member of the pressing forcetransmission mechanism 21H in this embodiment. That means, as describedabove, the pressing force transmission mechanism 21H has the thrust ring33 on the upper side of the base plate 3 to transmit the pressing forcein the axial movement direction.

The splined shaft 35 may be directly joined to the first wedge plate 83Hand the thrust ring 33 as described in the embodiments, and the splinedshaft 35 may be indirectly joined via other members. It is also possibleto join a pressing bottom member and a pressing upper member, which areformed separately from the first wedge plate 83H and the thrust ring 33,to the splined shaft 35 to form a locked linkage, and join the pressingbottom member and the pressing upper member to the first wedge plate 83Hand the thrust ring 33 in the axial movement direction.

The second wedge plate 81H converts and transmits the force by its wedgeeffect against the first wedge plate 83H by the driving force outputfrom the pressing drive source such as the pressing drive motor and theair cylinder. The second wedge plate 81H is formed into a substantiallysame shape as the first wedge plate 83H.

The second wedge plate 81H has an inclined surface 81Haa (81Hba). Theinclined surface 81Haa (81Hba) is opposed to the inclined surface 79Ha(79Hb) of the first wedge plate 83H.

Therefore, when the driving force output from the pressing drive motoror the air cylinder is transmitted to the second wedge plate 81H, theforce produced by the linear movement of the second wedge plate 81H canbe transmitted as the pressing force in the axial movement direction ofthe polishing plate 5 via the first wedge plate 83H by the wedge effectbetween the inclined surface 81Haa (81Hba) and the inclined surface 79Ha(79Hb). Thus, the operational effect similar to the above-describedembodiments can be obtained.

In the wedge plate and the surrounding structure shown in FIG. 37, thefirst and second wedge plates 83H, 81H are respectively supported byfirst and second linear guides 171, 173. The first linear guide 171 isformed by a guide rail 171 a and a block 171 b, and the second linearguide 173 is formed by a guide rail 173 a and a block 173 b.

The guide rail 171 a of the first linear guide 171 is fixed to each ofinclined surfaces 81Haa, (81Hba) of the second wedge plate 81.

The block 171 b of the first linear guide 171 is fixed to each of theinclined surfaces 79Ha, (79Hb) of the first wedge plate 83H.

The block 173 b of the second linear guide 173 is fixed to each of theflat bottom surfaces 81Hab, (81Hbb) of the second wedge plate 81H.

The guide rail 173 a of the second linear guide 173 is attached to afixed side such as a base plate 3 side via a bracket and the like.

The second wedge plate 81H is joined to a direct motion member having asimilar structure to the direct motion member 61 in Embodiment 1 orjoined to the piston rod of the air cylinder via a connection member175.

Therefore, the driving force output from the pressing drive motor or theair cylinder is transmitted to the second wedge plate 81H and the secondwedge plate 81H is moved. The second wedge plate 81H is moved smoothlyby the block 173 b running on the guide rail 173 a of the second linearguide 173.

When the second wedge plate 81H is moved, the guide rail 171 a of thefirst linear guide 171 is integrally moved.

The block 171 b of the first linear guide 171 is not moved in the linearmovement direction of the second wedge plate 81H. Therefore, in responseto the movement of the guide rail 171 a, the wedge effect occurs, andthe first wedge plate 83H transmits the pressing force in a directionshown by an arrow in the splined shaft 35. The transmission of thepressing force causes the pressing force transmission mechanism 21H inFIG. 36 to function, for example.

The wedge mechanism 59H may be arranged upside down. In sucharrangement, the first wedge plate 83H is joined to the fixed side, andthe guide rail 173 a of the second linear guide 173 is joined and fixedto the splined shaft 35. The wedge mechanism 59H may be formed into aunit, and the unit may be removably arranged between the splined shaft35 and the base plate 3.

In the end face polishing device for optical fiber ferrule in FIG. 38,the holder plate 109 is included in a pressing force transmissionmechanism 21I. The basic structure of a wedge mechanism 59I is similarto the wedge mechanism 59H in FIG. 37. Therefore, the same referencenumerals are denoted to the corresponding components. For some referencenumerals, “I” is denoted instead of “H”, and the overlapped explanationsare omitted.

In FIG. 38, the wedge mechanism 59I is used for a structure of movingthe post 9F shown in FIG. 32 vertically in the top-and-bottom directionwith respect to the polishing plate 5.

In this case, a first wedge plate 3Fc is fixed to a base plate 3F on thefixed side unlike the first wedge plate 83H in FIG. 37, and the firstwedge plate 3Fc serves as a member on the fixed side. Consequently, thereference numeral of the first wedge plate 3Fc is changed from thereference numeral of the corresponding member.

The guide rail 173 a of the second linear guide 173 is fixed to atransmission plate 83I. In this example, the transmission plate 83Icorresponds to the cam structure 83 shown in FIG. 9 of Embodiment 1.Therefore, a flat upward coupling face 89I is formed on the transmissionplate 83I.

The bottom end of the axial movement guide 9Fa is joined and fixed tothe flat coupling face 89I of the first wedge plate 83I in a similarstructure to Embodiment 1.

With the above described fixing, four axial movement guide 9Fa and theposts 9F, the transmission plate 83I, and the holder plate 109 form alocked linkage. In the above described locked linkage, when the secondwedge plate 81I is driven, a load received by the first wedge plate 3Fcin the top-and-bottom direction is received by the base plate 3F. Theload received by the base plate 3F is transmitted as a reaction forcewith rigidity via the wedge mechanism 59I to the coupling face 89I, thefour axial movement guide 9Fa, the posts 9F and the holder plate 109.

In this case, the transmission plate 83I forms a pressing bottom memberof the pressing force transmission mechanism 21I in this embodiment.That means, as described above, the pressing force transmissionmechanism 21I has the transmission plate 83I on the lower side of thebase plate 3F to transmit the pressing force in the axial movementdirection.

In addition, the holder plate 109 forms a pressing upper member of thepressing force transmission mechanism 21I in this embodiment. Thatmeans, as described above, the pressing force transmission mechanism 21Ihas the holder plate 109 on the upper side of the base plate 3F totransmit the pressing force in the axial movement direction.

The axial movement guide 9Fa may be directly joined to the transmissionplate 83I as described in the embodiments, and the axial movement guide9Fa may be indirectly joined via other members.

The wedge mechanism 59I may be arranged upside down. In sucharrangement, the first wedge plate 3Fc is joined and fixed to thetransmission plate 83I, and the guide rail 173 a of the second linearguide 173 is joined and fixed to the base plate 3F. The wedge mechanism59I may be formed into a unit, and the unit may be removably arrangedbetween the transmission plate 83I and the base plate 3F. Therefore, inthis embodiment, it is possible to generate a large pressing load from asmall driving force by the use of the wedge mechanisms 59H, 59I. Thiseffect contributes to simplify the structure and realize a compactdevice.

Further, the operational effect similar to Embodiment 1 can be obtained.

DESCRIPTION OF THE REFERENCE NUMERALS

-   1, 1A, 1E, 1F, 1G: end face polishing device for optical fiber    ferrule,-   3, 3E, 3F: base plate (base portion),-   5, 5F: polishing plate,-   5 c: bearing hole (bearing portion)-   9: post (holding portion)-   9F: post (holding portion, pressing force transmission mechanism),-   9Fa: axial movement guide (holding portion guiding support part    (pressing force transmission mechanism),-   15: pressing drive motor (pressing drive source),-   15G: air cylinder (pressing drive source),-   21, 21A, 21G, 21H, 21I: pressing force transmission mechanism,-   22, 22G: controller,-   23: revolution drive shaft,-   29: ball guide (bearing portion),-   30: bearing portion,-   33, 33E, 33F, 33G: thrust ring (polishing plate guide supporting    portion, pressing force transmission mechanism, pressing upper    member),-   33 c: downward coupling face,-   35: splined shaft (axial movement guide, polishing plate guide    supporting portion, pressing force transmission mechanism),-   57: direct motion mechanism,-   59, 59A, 59B: cam mechanism,-   59H, 59I: wedge mechanism,-   61: direct motion member,-   63: linear motion guide,-   77, 77A: load cell (sensor),-   79, 79A, 79B, 79C, 79D: cam portion (cam mechanism),-   79 a, 79 b, 79Aa, 79Ab, 79Ba, 79Bb, 79Ca, 79Cb, 79Da, 79Db: inclined    surface (cam mechanism),-   81, 81A, 81B: cam drive portion (cam mechanism),-   81 a, 81 b, 81Aa, 81Ab, 81Ba, 81Bb: cam follower (cam mechanism),-   83, 83A, 83B, 83C, 83D, 83F: cam structure (cam mechanism, pressing    bottom member),-   81H, 81I: second wedge plate,-   83H: first wedge plate (pressing bottom member),-   83I: transmission plate (pressing bottom member),-   89, 89A: upward coupling face,-   107: polishing jig,-   109 holder plate (pressing upper member)-   109 a: downward coupling face,-   169: pressurization plate (pressing bottom member).

The invention claimed is:
 1. An end face polishing device for opticalfiber ferrule for polishing an end face of an optical fiber ferrule byapplying a polishing pressure between a polishing plate driven by apolishing drive shaft and an optical fiber ferrule held by a holdingportion, the end face polishing device for optical fiber ferrulecomprising: a bearing portion for allowing the polishing plate to rotaterelatively around the polishing drive shaft and to move relatively tothe polishing drive shaft in an axial direction; a polishing plate guidesupporting portion movable only in an axial movement direction of thepolishing plate for movably supporting the polishing plate on a baseportion to apply the polishing pressure to the holding portion byallowing the polishing plate to move in the axial direction; a pressingdrive source for adjustably outputting a driving force to apply thepolishing pressure; and a pressing force transmission mechanism fortransmitting the driving force output from the pressing drive source asa pressing force in the axial movement direction of the polishing platevia the polishing plate guide supporting portion.
 2. The end facepolishing device for optical fiber ferrule according to claim 1, whereinthe polishing drive shaft includes a revolution drive shaft fitted in acenter portion of the polishing plate to make the polishing platerevolve while allowing a self-rotation of the polishing plate, and thebearing portion allows the polishing plate to rotate relatively aroundthe revolution drive shaft and to move relatively to the revolutiondrive shaft in the axial direction.
 3. The end face polishing device foroptical fiber ferrule according to claim 1, wherein the polishing plateguide supporting portion has a thrust ring and an axial movement guide,the thrust ring supports an outer peripheral portion of a bottom surfaceof the polishing plate by a plane surface to serve as a part of thepressing force transmission mechanism for transmitting the pressingforce while allowing the polishing plate to be driven, and the axialmovement guide is joined to the thrust ring at one end of the axialmovement guide and movably supported by the base portion to serve as apart of the pressing force transmission mechanism for transmitting thepressing force from the other end of the axial movement guide.
 4. Theend face polishing device for optical fiber ferrule according to claim3, wherein the pressing force transmission mechanism includes a directmotion mechanism and a cam mechanism, the direct motion mechanism beingsupported by the base portion, the direct motion mechanism includes: adirect motion member which performs a linear movement in a directioncrossing the axial movement direction by the transmitted pressing force;and a linear motion guide for supporting the direct motion member on thebase portion to allow the linear movement, and the cam mechanismperforms a cam action to convert and transmit a force generated by thelinear movement of the direct motion member to a pressing force in theaxial movement direction.
 5. The end face polishing device for opticalfiber ferrule according to claim 4, wherein the cam mechanism includes acam portion and a cam drive portion which perform the cam action, thecam portion includes an inclined surface provided in a cam structure,the cam structure is joined to the other end of the axial movement guideto convert and transmit the force generated by the linear movement ofthe direct motion member, and the cam drive portion is supported by thedirect motion member and abutted with the inclined surface to transmitthe force generated by the linear movement of the direct motion memberto the inclined surface.
 6. The end face polishing device for opticalfiber ferrule according to claim 3, wherein the pressing forcetransmission mechanism includes a wedge mechanism which performs a wedgeeffect for transmitting a force generated by a linear movement as thepressing force in the axial movement direction.
 7. The end facepolishing device for optical fiber ferrule according to claim 3, whereinthe pressing force transmission mechanism has a pressing bottom memberon a lower side of the base portion for transmitting the pressing forcein the axial movement direction, the pressing bottom member has a flatupward coupling face which extends in a front-and-back direction of thelinear movement so as to cross the axial movement direction, and theaxial movement guides are fixed directly or indirectly to the upwardcoupling face.
 8. The end face polishing device for optical fiberferrule according to claim 7, wherein the pressing force transmissionmechanism has a pressing upper member on an upper side of the baseportion for transmitting the pressing force in the axial movementdirection, the pressing upper member has a downward coupling face whichextends in the front-and-back direction of the linear movement, theaxial movement guides are fixed directly or indirectly to the downwardcoupling face, and the pressing bottom member, the axial movement guidesand the pressing upper member form a locked linkage.
 9. The end facepolishing device for optical fiber ferrule according to claim 1, whereinthe polishing plate guide supporting portion has a thrust ring and aguide ring, the thrust ring supports an outer peripheral portion of abottom surface of the polishing plate by a plane surface to serve as apart of the pressing force transmission mechanism for transmit thepressing force while allowing the polishing plate to be driven, theguide ring movably supports the thrust ring on the base portion totransmit the pressing force in the axial movement direction, thepressing force transmission mechanism has a driving ring on the baseportion, the driving ring being arranged at a bottom part of the thrustring so as to be opposed to the thrust ring, the driving ring beingdriven by the driving force to rotate around a rotational shaftextending along the axial movement direction, and the thrust ring has anend face cam provided between the thrust ring and the driving ring tomake the thrust ring move in the axial movement direction fortransmitting the pressing force when the driving ring rotates.
 10. Theend face polishing device for optical fiber ferrule according to claim1, wherein the pressing drive source is a pressing drive motor or an aircylinder.
 11. The end face polishing device for optical fiber ferruleaccording to claim 1, wherein, the pressing drive source is an aircylinder, and the pressing force transmission mechanism transmits thepressing force so that an output direction of the air cylinder coincideswith the axial movement direction.
 12. The end face polishing device foroptical fiber ferrule according to claim 1, further comprising: a sensorprovided in the pressing force transmission mechanism, the sensordetecting the polishing pressure directly or indirectly, a controllerfor controlling the pressing drive source to adjust the polishingpressure detected by the sensor to a predetermined polishing pressure.13. An end face polishing device for optical fiber ferrule for polishingan end face of an optical fiber ferrule by applying a polishing pressurebetween a polishing plate driven by a polishing drive shaft and anoptical fiber ferrule held by a holding portion, the end face polishingdevice for optical fiber ferrule comprising: a bearing portion forallowing the polishing plate to rotate relatively around the polishingdrive shaft and to move relatively to the polishing drive shaft in anaxial direction; a polishing plate guide supporting portion for movablysupporting the polishing plate on a base portion to apply the polishingpressure to the holding portion by allowing the polishing plate to movein the axial direction; a pressing drive source for adjustablyoutputting a driving force to apply the polishing pressure; and apressing force transmission mechanism for transmitting the driving forceoutput from the pressing drive source as a pressing force in an axialmovement direction of the polishing plate via the polishing plate guidesupporting portion, wherein a drive source to rotate the polishing driveshaft is fixed on the base portion.
 14. An end face polishing device foroptical fiber ferrule for polishing an end face of an optical fiberferrule by applying a polishing pressure between a polishing platedriven by a polishing drive shaft and an optical fiber ferrule held by aholding portion, comprising: a holding portion guiding support part formovably supporting the holding portion on a base portion to apply thepolishing pressure to the polishing plate by allowing the holdingportion to move in an axial direction; a pressing drive source foradjustably outputting a driving force to apply the polishing pressure;and a pressing force transmission mechanism for transmitting the drivingforce output from the pressing drive source as a pressing force in anaxial movement direction of the holding portion, wherein the holdingportion guiding support part has axial movement guides, one end side ofeach of the axial movement guides is joined to a post for attaching apolishing jig used for fixing the optical fiber ferrule, and each of theaxial movement guides is movably supported by the base portion to serveas a part of the pressing force transmission mechanism for transmittingthe pressing force from the other end.
 15. The end face polishing devicefor optical fiber ferrule according to claim 14, wherein the pressingforce transmission mechanism includes a direct motion mechanism and acam mechanism, the direct motion mechanism being supported by the baseportion, the direct motion mechanism includes: a direct motion memberwhich performs a linear movement in a direction crossing the axialmovement direction by the transmitted pressing force; and a linearmotion guide for supporting the direct motion member on the base portionto allow the linear movement; and the cam mechanism performs a camaction to convert and transmit a force generated by the linear movementof the direct motion member to a pressing force in the axial movementdirection.
 16. The end face polishing device for optical fiber ferruleaccording to claim 15, wherein the cam mechanism includes a cam portionand a cam drive portion which perform the cam action, the cam portionincludes an inclined surface provided in a cam structure, the camstructure is joined to the other end of the axial movement guide toconvert and transmit the force generated by the linear movement of thedirect motion member, and the cam drive portion is supported by thedirect motion member and abutted with the inclined surface to transmitthe force generated by the linear movement of the direct motion memberto the inclined surface.